Class 08 Activity – Happy Numbers

A happy number is one for which the sum of the squares of its digits ends in 1 after repeated squaring and adding as shown below. Is 13 a happy number? 

1² + 3² = 10 and then 1² + 0² = 1. 

Yes, 13 is a happy number. 

Sometimes many repetitions are necessary.

Is 44 a happy number?

4² + 4² = 3² and 3² + 2² = 13 and 1² + 3² = 10 and 1² + 0² = 1. Yes.

Is your house number a happy number?

Is your telephone number a happy number?

Is your birthdate a happy number?

Is today's date a happy number?

A happy number name, or word, is found by giving each letter of the alphabet a number, i.e.,

A B C D …... Z

1 2 3 4 …… 26

Is MATHS a happy number word?

MATHS is 13 1 20 8 19.

13² + 12²+ 202+8² + 19² = 995

 and 9² +9²+ 5² = 187 etc. 

Continue to find whether MATHS is a happy number word.

Which days of the week are happy number days? 

Which months of the year are happy number months?

Is your name a happy number word? 

Is the name of your city or town or district a happy number name?