Class 10 Math Real Numbers - 2024

If the HCF (2520, 6600) = 40 and LCM (2520, 6600) = 252 × k, then the value of k is

• 1650

• 1600

• 165

• 1625

If a = 2² × 3^x, b = 2² × 3 × 5, c = 2² × 3 × 7 and LCM (a, b, c) = 3780, then x is equal to

• 1

• 2

• 3

• 0

A pair of irrational numbers whose product is a rational number is :

• (√16, √4)

• (√5, √2)

• (√3, √27)

• (√36, √2)

The smallest irrational numbers by which √20 should be multiplied so as to get a rational number, is:

• √20

• √2

• 5

• √5

The HCF of two numbers 65 and 104 is 13. If LCM of 65 and 104 is 40x, then the value of x is:

• 5

• 13

• 40

• 8

If 3825 = 3^x × 5^y × 17^z, then the value of x + y - 2z is:

• 0

• 1

• 2

• 3

The greatest number which divides 281 and 1249, leaving the remainder 5 and 7 respectively, is:

• 23

• 276

• 138

• 69

The LCM of three numbers 28, 44, and 132 is:

• 258

• 231

• 462

• 924

If the product of two co-prime numbers is 553, then their HCF is :

• 1

• 553

• 7

• 79

If the prime factorization of 2520 is 2³× 3^a × b × 7, then the value of a + 2b is :

• 12

• 10

• 9

• 7