Alike: They both find what's in common.
Difference: LCM finds the least multiple while GCF finds the greatest factor.
The answer is 30
2 * 15 = 30
5 * 6 = 30
30 is between 24 and 34
The only rule to follow is
Divide dividend by divisor and the mention the quotient and things left after remains in place of remainder
Here is a sample

Answer: -2x + 9
First, Use the distributive property: 3(x+3)-5x (3 multiplied by x is 3x and 3 multiplied by 3 is 9
Next, subtract the variable x: 3x+9-5x (3x-5x=-2x
The answer is -2x+9