In the lcm of 3a^2b^4c^5 and 7a4bc^2, what is the exponent on the b?

a)1
b)4
c)5
d)6

sorry that i suck at math! ~ -katie

In arithmetic and number theory, the least common multiple, lowest common multiple, or smallest common multiple of two integers a and b, usually denoted by LCM(a, b), is the smallest positive integer that is divisible by both a and b. so the LCM of 3a^2b^4c^5 and 7a4bc^2

is a^2bc^2

so the exponent of b is 1