How do I get the answer to (3/5 - 3/10) x 30=

Question

I need to know how to get the answer to the math problem above.

 

Answer 1

Hi Jessie,

Accoding to the order of operations we need to do what is inside the parenthesis first, so we need to subtract 3/10 from 3/5.

To do this we need an LCD or Least Common Denominator, which in this case is 10.  Now what ever to do to the bottom of the fraction make it ten we need to do to the top as well.

So now we end up with:

 

6/10 (we multiplied the 5 times 2 to get ten and because we did that to the bottom, the denominator, we need to do it to the top, the numerator so we got 6/10.

 

so 6/10-5/10=

take that answer and multiply by 30 and you will have your answer.

Answer 2

Jessie, there are two different ways to do this problem, but the easiest is to do the distributive property.  If I have (5 + 7) x 3, I would usually use PEMDAS and get 12 x 3 = 36.

 

Or, we can split what's inside the parentheses and multiply each by 3.  5 x 3 + 7 x 3 = 15 + 21 = 36.

 

Let's do the latter with your problem.  3/5 x 30 - 3/10 x 30.  90/5 - 90/10 = 18 - 9 = 9.

 

Hope this helps!