HARD
Earn 100

Find all pairs of positive integers whose sum is 91 and H.C.F is 13. Show your work.

Important Questions on Less Common Multiple and Highest Common Factor

MEDIUM
The largest number which divides 72 and 127 leaving remainders 7 and 10 respectively is
MEDIUM
The product of two numbers is 2160 and their HCF is 12. If the sum of the squares of the two numbers is 4896, then what is the mean of the two numbers?
EASY
If x×y denotes H.C.F. of x and y and x@y denotes L.C.M. of x and y, then the value of 72×84@144 is:
HARD
If x+k is the HCF of x2+px+q and  x2+qx+p where pqthen what is the value of k?
MEDIUM

If the HCF of polynomials fx=x-1x2+3x+a and gx=x+2x2+2x+b is x2+x-2 then what are the values of a and b respectively?

EASY
The LCM and HCF of two numbers are 171360 and 14 respectively. If one of the numbers is 2142 then what is the second number? 
EASY
What is the HCF of smallest prime number and the smallest composite number ?
EASY
A, B, C have 152,171 and 266 marbles, respectively. They decide to divide these marbles in parts such that all parts have the same number of marbles. Also, they cannot give or take the marbles. Find the minimum possible number of parts that can be made.
EASY
Three numbers are in the ratio 1:2:3 and their HCF is 12 . The numbers are_____.
EASY
At a telephone exchange, three phones ring at intervals of 20 sec, 24 sec, and 30 sec. If they ring together at 11:25 am, when will they next ring together?
MEDIUM
Find the number lying between 900 and 1000, which when divided by 38 and 57 leaves in each case a reminder 23.