Class 10 QUIZ REAL NUMBERS

 The prime factorisation of  120 is

  2^2×5 

   2^2×5×3

   2^2×5^2×3

  3^2×5^2×2^2

Answer : B  

The prime factorisation of 375 is

  5^2×3^2×2^2

  5×3×2

  5^2×2^2×3

  5^2×3^2×2

Answer : C  5^2×2^2×3  

If the prime factorization of 1440 is 2^5×6^2×5, then the value of b is

  3

  3^2

  3^3

  +5

Answer : A  3

If the prime factorization of 380 is a^2 bc then the value of a^2,b,c is

  2,5,19

  2,5,9

  12,5,9

  2,15,19

Answer : A 

If the prime factorization of 22275 is 3^a×5^b×〖11〗^c, then the value of a,b,c is

  a=5, b=2, c=1

   a=+3, b=2, c=1

  a=5, b=2, c=4

  a=4, b=2, c=1

Answer : D  a=4, b=2, c=1

The prime factorization of 12716 is

  2×11×17

  2^2×〖11〗^2×〖17〗^2

  2^2×11×〖17〗^2

  2×〖11〗^2×〖17〗^2

      Answer : C  2^2×11×〖17〗^2

The prime factorization of 3690 is

  5×3×2×41

  5^2×3^2×2×41

  5×3^2×2×41

  5×3^2×2^2×41

      Answer : C  5×3^2×2×41

If HCF (33,45) is 3, then the LCM (33,45) is

  459

  495

  49

  45

Answer : B  495

If the LCM of (64,40) is 320, then the HCF (64,40) is

  8

  9

  10

  5

Answer : A  8

If the LCM (a,b) is 36 and HCF (a,b) is 6 then (a×b) is

  217

  271

  216

  261

Answer : C  216