Given that HCF(253,  440) = 11 and LCM(253, 440) = 253×R. The value of R is:

(a) 400

(b) 40

(c) 440

(d) 253

If p, q are two consecutive natural numbers, then HCF(p, q) is:

(a) q

(b) p

(c) 1

(d) pq

 \((\sqrt{2}-\sqrt{3})(\sqrt{3}+\sqrt{2})\) is:

(a) A rational number 

(b) a whole number

(c) an irrational number 

(d) a natural number

HCF and LCM of a and b are 19 and 152 respectively. If a=38, then b is equal to:

(a) 152

(b) 19   

(c) 38

(d) 76

The largest number which divides 71 and 126, leaving remainders 6 and 9 respectively is:

(a) 1750

(b) 13 

(c) 65 

(d) 875

If two positive integers p and q can be expressed as p=ab² and q=a³b, a, b being prime numbers, then LCM(p, q) is:

(a) ab    

(b) a²b²                                                                               

(c) a³b²                                                           

(b) a³b³

The least number that is divisible by all the numbers from 1 to 10 (both inclusive) is:

(a) 10

(b) 100                                   

(c) 504 

(d) 2520

If p, q are two prime numbers, then LCM(p, q) is:

(a) 1

(b) p

(c) q

(d) pq

If two integers a and b are written as a = x³y² and b = xy⁴; x, y are prime numbers, then H.C.F.(a, b) is:

(a) x³y³ 

(b) x²y²

(c) xy

(d) xy²

If \(x=2^3 \times 3 \times 5^2\), \(y=2^2 \times 3^3\), then HCF(x, y) is:

(a) 12

(b) 108

(c) 6

(d) 36