Question:The product of two 2-digit numbers is 2028 and their G.C.M. is 13. The numbers are:
A 26,78
B 39,52
C 13,156
D 36,68
/49
+ Answer
B
+ Explanationsolution:
Let the numbers be 13a and 13b.Then,
`13a xx 13b=2028`
`=> ab=12`.
Now, co-primes with product 12 are (1,12) and (3,4).
So, the numbers with H.C.F. 13 and product 2028 are:
`(13 xx 1, 13 xx 12) and (13 xx 3, 13 xx 4)`.
`:.` Required 2-digit numbers are 39 & 52.