Decimals · 11+ GL Assessment
1. Understanding Place Value
The key to decimals is understanding that each digit to the right of the decimal point represents a fraction with a denominator of 10, 100, 1000, etc.
4 is 4 tens (40) · 5 is 5 units (5) · 3 is 3 tenths (3/10 or 0.3) · 6 is 6 hundredths (6/100 or 0.06) · 7 is 7 thousandths (7/1000 or 0.007)
So, 45.367 = 40 + 5 + 0.3 + 0.06 + 0.007
2. Adding & Subtracting Decimals
Golden Rule: Line up the decimal points! You can add zeroes to the right to help keep everything aligned.
12.45
+ 3.80
--------
16.25
7.50
- 2.34
--------
5.16
3. Multiplying Decimals
- Multiply the numbers as if they were whole numbers (ignore decimal points).
- Count the total number of decimal places in both original numbers.
- Place the decimal point in your answer so it has the same total number of decimal places.
1. 13 × 25 = 325
2. 1.3 has 1 decimal place, 0.25 has 2. Total = 3 decimal places.
3. Answer: 0.325
4. Dividing Decimals
The easiest way is to make the divisor a whole number.
1. Multiply both numbers by 10 (to make the divisor, 0.4, a whole number): 68.4 ÷ 4
2. Now do the division: 4 goes into 6 one time (1), remainder 2. Bring down 8, making 28. 4 goes into 28 seven times (7). Bring down 4. 4 goes into 4 one time (1).
3. The answer is 17.1
5. Converting between Decimals, Fractions & Percentages
0.7 = 7/10 · 0.35 = 35/100 = 7/20 · 0.125 = 125/1000 = 1/8
3/4 = 3 ÷ 4 = 0.75 · 1/8 = 1 ÷ 8 = 0.125
0.89 = 0.89 × 100 = 89% · 0.04 = 4%
75% = 75 ÷ 100 = 0.75 · 5% = 0.05
Part 2: 10 Practice Questions (Mixed Sub-topics)
- 1. What is the value of the 7 in the number 12.374?
- 2. Calculate 5.67 + 12.3
- 3. Calculate 8.4 - 2.57
- 4. Calculate 3.5 × 0.6
- 5. Calculate 9.1 ÷ 0.05
- 6. Convert 0.65 to a fraction in its simplest form.
- 7. Convert 3/8 to a decimal.
- 8. Convert 0.08 to a percentage.
- 9. Sarah buys a book for £5.75 and a pen for £1.20. How much change does she get from £10?
- 10. A piece of ribbon is 2.5m long. How many 0.4m lengths can be cut from it?
Part 3: 50+ Additional Practice Questions
Place Value & Ordering
- 11. Write 15.068 in words.
- 12. What is the digit in the hundredths place in 203.951?
- 13. Arrange in ascending order: 0.6, 0.59, 0.608, 0.07
- 14. Which is larger: 4.099 or 4.1?
- 15. Round 12.478 to the nearest tenth.
- 16. Round 5.635 to 2 decimal places.
- 17. What number is half-way between 2.7 and 2.8?
- 18. Write down the smallest number you can make using the digits 4, 0, 9, and 1 and a decimal point.
Addition & Subtraction
- 19. 14.8 + 6.35
- 20. 22 + 3.07 + 0.9
- 21. 10.04 - 3.8
- 22. 5 - 2.76
- 23. 12.3 - 4.88
- 24. Alan is 1.45m tall. His sister is 1.3m tall. What is the difference in their heights?
- 25. The temperature was 5.8°C. It rose by 3.5°C. What is the new temperature?
Multiplication
- 26. 6.2 × 4
- 27. 1.5 × 0.7
- 28. 0.8 × 0.08
- 29. 12.5 × 1.1
- 30. 0.04 × 0.3
- 31. A pencil costs £0.35. How much do 6 pencils cost?
- 32. One litre of petrol costs £1.48. How much does 5 litres cost?
- 33. A square has a side length of 3.2cm. What is its perimeter?
Division
- 34. 15.6 ÷ 3
- 35. 9.1 ÷ 7
- 36. 4.5 ÷ 0.5
- 37. 6 ÷ 0.4
- 38. 0.81 ÷ 0.9
- 39. 2.4 ÷ 0.03
- 40. £10.50 is shared equally between 3 people. How much does each get?
- 41. A 2.5kg bag of flour is divided into 5 equal pots. How much flour is in each pot?
Conversions & Mixed Applications
- 42. Convert 3/5 to a decimal.
- 43. Convert 0.92 to a fraction in its simplest form.
- 44. Convert 7/20 to a percentage.
- 45. Convert 5% to a decimal.
- 46. Convert 0.375 to a fraction.
- 47. What is 25% of 3.6?
- 48. Find 1/4 of 8.4
- 49. A shirt costs £24. In a sale, there is a 15% discount. How much is the discount?
- 50. In a class of 30, 40% are girls. How many boys are there?
- 51. A recipe needs 0.3kg of flour. If you are making 1.5 times the recipe, how much flour do you need?
- 52. A car uses 0.12 litres of fuel for every kilometre. How much fuel is needed for a 45km journey?
Part 4: 10 Previous Year GL Assessment Style Questions
- 1. Calculate 14.07 - 8.4 A) 6.67 B) 5.67 C) 6.47 D) 5.87
- 2. What is 3.25 × 0.6? A) 1.95 B) 19.5 C) 0.195 D) 195
- 3. Convert the fraction 4/25 to a decimal. A) 0.16 B) 0.4 C) 0.04 D) 0.625
- 4. A box of 12 yoghurts costs £4.80. What is the cost of one yoghurt? A) £0.36 B) £0.40 C) £0.48 D) £4.00
- 5. Which of these numbers is the largest? A) 5.099 B) 5.9 C) 5.91 D) 5.1
- 6. What is 4.56 ÷ 8? A) 5.7 B) 0.57 C) 0.75 D) 57
- 7. In a sports day race, Ben's time was 14.8 seconds, Amy's was 15.02 seconds, and Tom's was 14.75 seconds. Who won? A) Ben B) Amy C) Tom D) Cannot tell
- 8. What is 15% written as a decimal? A) 0.015 B) 0.15 C) 1.5 D) 15.0
- 9. A bag of sweets weighs 0.35kg. What is the total weight of 6 such bags? A) 2.1kg B) 1.8kg C) 21kg D) 3.5kg
- 10. Which calculation does NOT give the same answer as 0.4 × 12? A) 4 × 1.2 B) 40 × 0.12 C) 0.04 × 120 D) 0.2 × 24
Answer Key & Solutions — Part 2 & Part 4
Part 2 · 10 Practice
Part 4 · GL Style
Additional Practice: Sections A – H
Section A: Place Value & Ordering
- 1. What is the value of the digit 8 in the number 24.083?
- 2. Write the number seven and twenty-four thousandths in digits.
- 3. Which number is exactly halfway between 4.7 and 4.8?
- 4. Arrange in ascending order: 0.099, 0.9, 0.89, 0.0999.
- 5. Round 6.4781 to the nearest hundredth.
- 6. Which is larger: 5.060 or 5.006?
- 7. Write 0.375 as a fraction in its simplest form.
- 8. What is the next number in the sequence: 6.5, 6.45, 6.4, 6.35, ...?
- 9. How many hundredths are there in 3.5?
- 10. Which number has the greatest value in the thousandths place: 8.235, 8.325, 8.532, 8.253?
Section B: Addition & Subtraction
- 11. 15.8 + 4.67 + 0.3 =
- 12. 20.01 - 3.8 =
- 13. 7 - 2.345 =
- 14. 12.4 + 5.08 + 0.9 =
- 15. 8.5 - 4.67 =
- 16. 10.1 - 0.99 =
- 17. 6.7 + 12.35 + 1.002 =
- 18. 25.4 - 12.75 =
- 19. 4.2 + 3.05 + 0.8 =
- 20. 9.06 - 5.7 =
Section C: Multiplying & Dividing
- 21. 4.5 × 0.8 =
- 22. 0.6 × 0.07 =
- 23. 12.5 × 1.2 =
- 24. 3.24 ÷ 6 =
- 25. 4.8 ÷ 0.4 =
- 26. 0.81 ÷ 0.9 =
- 27. 7.5 × 0.4 =
- 28. 6.3 ÷ 0.07 =
- 29. 0.125 × 8 =
- 30. 5.6 ÷ 0.08 =
Section D: Conversions & Mixed Applications
- 31. Convert 0.88 to a fraction in its simplest form.
- 32. Convert 7/8 to a decimal.
- 33. Convert 0.03 to a percentage.
- 34. What is 30% of 8.5?
- 35. Express 19/20 as a decimal.
- 36. Write 0.075 as a fraction in its simplest form.
- 37. What is 15% of 4.0?
- 38. Convert 1.25 to a mixed number.
- 39. What is 1/5 of 7.5?
- 40. Convert 0.004 to a percentage.
Section E: Mixed Problem Solving
- 41. A piece of string is 3.6m long. If I cut off 1.45m, how much is left?
- 42. One apple costs £0.28. How much do 6 apples cost?
- 43. A box of 24 pencils costs £7.20. What is the cost per pencil?
- 44. A car travels 84.5 miles on 6.5 gallons of petrol. How many miles per gallon does it do?
- 45. The perimeter of a square is 15.6cm. What is the length of one side?
- 46. A bag of sugar weighs 2.4kg. If I use 0.85kg in a recipe, how much is left?
- 47. A book has 240 pages. If I have read 0.65 of the book, how many pages have I read?
- 48. A bottle holds 2.25 litres of water. How many 0.25 litre glasses can be filled from it?
- 49. A rectangle has a length of 5.2cm and a width of 3.5cm. What is its area?
- 50. A packet of crisps weighs 0.35kg. How much would 8 packets weigh?
Section F: Mixed Word Problems & Multi-step
- 51. Tom buys a magazine for £2.85 and a drink for £1.40. He pays with a £5 note. How much change does he get?
- 52. A piece of rope is 8m long. I cut off 3 pieces each of 1.25m. How much rope is left?
- 53. A box of 36 chocolates costs £12.60. What is the cost per chocolate?
- 54. A car uses 0.065 litres of fuel per kilometre. How much fuel is used for a 60km journey?
- 55. A shop reduces a £60 coat by 20%. What is the new price?
- 56. A recipe for 6 people requires 0.75kg of flour. How much flour is needed for 10 people?
- 57. A tank holds 120 litres. It is being filled at a rate of 7.5 litres per minute. How long will it take to fill?
- 58. A packet of biscuits contains 15 biscuits. Each biscuit weighs 0.032kg. What is the total weight of the packet?
- 59. A train travels at a constant speed of 90km/h. How far does it travel in 1 hour and 15 minutes?
- 60. A rectangle has a perimeter of 24.8cm. If its length is 7.5cm, what is its width?
- 61. A bag of potatoes weighs 5.6kg. I remove 4 potatoes with a combined weight of 1.25kg. What is the new weight of the bag?
- 62. A bottle of juice contains 1.75 litres. I pour out 0.4 litres. How much juice is left?
- 63. A book costs £8.50. How many books can I buy with £50?
- 64. A bus has 52 seats. 0.75 of the seats are occupied. How many seats are empty?
- 65. A piece of wood is 4.8m long. I need to cut it into 0.3m lengths. How many full pieces can I get?
Section G: Fictional "Previous Year Paper" (50 Questions)
- 66. Calculate 13.4 + 7.65
- 67. What is 8.2 - 3.47?
- 68. Multiply 4.5 by 0.6
- 69. Divide 10.8 by 0.9
- 70. Round 7.269 to one decimal place.
- 71. Which is larger: 3.099 or 3.1?
- 72. Write 0.625 as a fraction in its simplest form.
- 73. Convert the fraction 3/5 to a decimal.
- 74. What is 40% of 6.5?
- 75. A box of 10 pencils costs £3.50. What is the cost of one pencil?
- 76. A car travels 72km in 1.2 hours. What is its average speed in km/h?
- 77. A rectangle measures 4.3cm by 6.2cm. What is its area?
- 78. A bag of flour weighs 1.5kg. I use 450g. How much flour is left in kilograms?
- 79. What is the perimeter of a square with a side length of 5.7cm?
- 80. A train ticket costs £14.75. I buy 2 tickets. How much change do I get from £40?
- 81. A bottle contains 2 litres of water. I drink 350ml. How much water is left in litres?
- 82. A cake recipe requires 0.45kg of butter. I want to make 1.5 times the recipe. How much butter do I need?
- 83. A packet of sweets costs £0.95. I buy 5 packets. How much change from a £10 note?
- 84. A bus has 48 seats. 5/8 of the seats are occupied. How many seats are empty?
- 85. A piece of ribbon is 5m long. I cut off 3 pieces, each 0.75m long. How much ribbon is left?
- 86. A book has 180 pages. I have read 2/3 of the book. How many pages have I read?
- 87. A box of 12 eggs costs £2.76. What is the cost per egg?
- 88. A car uses 0.08 litres of fuel for every kilometre. How much fuel is needed for a 250km journey?
- 89. A shirt costs £28.00. In a sale, it is reduced by 15%. What is the sale price?
- 90. A triangle has a base of 8cm and a height of 5.5cm. What is its area?
- 91. A bag of oranges weighs 3.2kg. I take out 3 oranges weighing 0.45kg in total. What is the new weight?
- 92. A jug contains 1.8 litres of milk. I pour 0.55 litres into a bowl. How much milk remains in the jug?
- 93. A pen costs £1.45. How many pens can I buy with £20?
- 94. A cycling race is 30km long. A cyclist has completed 0.7 of the race. How far has she cycled?
- 95. A plank of wood is 6m long. How many 0.4m lengths can be cut from it?
- 96. What is the value of the 4 in 19.046?
- 97. Write the number twelve and nine hundredths as a decimal.
- 98. Put these in order from smallest to largest: 2.02, 2.2, 2.002, 2.202
- 99. Calculate 0.1 × 0.1
- 100. Calculate 1.44 ÷ 1.2
- 101. Express 17/25 as a percentage.
- 102. Find 3/8 of 9.6
- 103. A TV programme starts at 7:35 pm and ends at 8:20 pm. How long does it last in hours?
- 104. A bag of 20 marbles weighs 0.5kg. What is the weight of one marble in grams?
- 105. A recipe needs 0.025kg of salt. How much salt is needed for 8 batches?
- 106. 5.67 × 100 =
- 107. 34.8 ÷ 1000 =
- 108. 0.07 × 0.3 =
- 109. 4.5 + ? = 10
- 110. ? - 3.75 = 2.8
- 111. 6.3 ÷ ? = 9
- 112. ? × 0.4 = 1
- 113. A digital clock shows 14:25. What time is this in 12-hour format?
- 114. In a class of 30 children, 18 are girls. What fraction of the class are boys?
- 115. A bathtub has 120 litres of water. 45 litres are removed. What percentage of the water remains?
Section H: 50 More GL Assessment Styles
- 116. Calculate: 23.4 - 7.89
- 117. What is 6.7 × 0.5?
- 118. Divide 8.4 by 0.07
- 119. Round 12.3456 to three decimal places.
- 120. Which number is the smallest: 0.101, 0.011, 0.11, 0.0111?
- 121. Convert 22/1000 to a decimal.
- 122. What is 12.5% of £40?
- 123. A bag of 5 lemons costs £1.10. What is the cost of one lemon?
- 124. A cube has a side of length 2.5cm. What is its volume?
- 125. The sum of two numbers is 15.6. One number is 8.9. What is the other number?
- 126. Write 4.5% as a decimal.
- 127. A pizza is cut into 8 equal slices. I eat 3 slices. What decimal of the pizza did I eat?
- 128. A coat costs £85. Its price is increased by 20%. What is the new price?
- 129. 0.3 + 0.03 + 0.003 =
- 130. 1 - 0.007 =
- 131. 2.5 × 40 =
- 132. 4.8 ÷ 12 =
- 133. 7.07 ÷ 10 =
- 134. 0.9 × 1000 =
- 135. Find the difference between 10 and 6.54.
- 136. What is the product of 2.5 and 3.2?
- 137. A triangle has an area of 24cm² and a base of 8cm. What is its height?
- 138. A pen is 13.5cm long. A pencil is 8.7cm long. How much longer is the pen?
- 139. A bottle holds 1.5 litres. A glass holds 0.2 litres. How many full glasses can be poured?
- 140. The temperature was -2°C. It rises by 5°C. What is the new temperature?
- 141. Which is heavier: 0.25kg or 350g?
- 142. A field is 40m long and 35.5m wide. What is the perimeter of the field?
- 143. 3/10 of a number is 9.3. What is the number?
- 144. A bus leaves at 10:15 am and arrives at 1:05 pm. How long is the journey?
- 145. A bag has 3 red, 5 blue, and 2 green balls. What is the probability of picking a blue ball?
- 146. Simplify the ratio 15:20.
- 147. A map scale is 1:25000. What is the actual distance if the map distance is 4cm?
- 148. A jacket was £60. It is in a sale with 1/3 off. What is the sale price?
- 149. 1.5 hours = ____ minutes.
- 150. 6500g = ____ kg.
- 151. 2.3km = ____ m.
- 152. 45mm = ____ cm.
- 153. 3/4 litre = ____ ml.
- 154. Find the mean of 4, 7, 5, 9, 5.
- 155. What is the range of the numbers in Q154?
- 156. (2.3 + 1.7) × 4 =
- 157. 5.6 - (2.1 + 0.9) =
- 158. 10 × (0.5 + 0.05) =
- 159. A number is multiplied by 10 and then 3 is added. The answer is 43. What was the original number?
- 160. The coordinates of a point are (3, 5). What are the coordinates after a reflection in the x-axis?
- 161. How many lines of symmetry does a square have?
- 162. What is the size of one interior angle of an equilateral triangle?
- 163. A roll of tape is 15m long. I use 7 pieces, each 0.85m long. How much tape is left?
- 164. A recipe for 4 people uses 2 eggs. How many eggs are needed for 10 people?
- 165. A number, when divided by 0.5, gives an answer of 16. What is the number?
Answer Key & Solutions — Sections A–H
Section A
Section B
Section C
Section D
Section E
Section F
Section G (66–115)
Section H (116–165)
Money, Length & Weight Problems (with Solutions)
Money Problems
Length Problems
Weight Problems
Key Tips for Decimal Problems
1. Line up decimal points when adding or subtracting.
2. Check units — convert all measurements to the same unit before calculating.
3. Money calculations — always include two decimal places for pounds.
4. Division — if dividing by a decimal, multiply both numbers to make the divisor a whole number.
5. Real-life context — consider whether the answer needs to be a whole number (e.g., pieces of wood).
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