LCM with variables and exponents??!?!?!?!?!!?

Question

i got this summer algabra packet and i don't know how to do like any of it!! Could you just explain how to do LCM with variables and exponents but don't give me answers? It would help me soooo much

Heres the problems:

1.) 4st, 10s

2.) 20c, 12c^2

[ ^ = exponent]

Answer 1

Ok, to explain it I'm going to use the second problem

- First factor each number into prime numbers and variables

20C = 2 , 2 , 5 , C

12C^2 = 2 , 2 , 3 , C , C

- Then count the number of times each factor occurs in each number

for 20C there are two 2s , one 5 , and one C

for 12C^2 there are two 2s , one 3 , and two Cs

- To get the LCM you have to use the highest occurance of each factor from all the numbers (I hope that makes sense)

there have to be at least two 2s , one 3 , one 5 , and two Cs

- Multiply those factors together, and that is the LCM

so multiply 2*2*3*5*C*C to get your answer