Marcus has 2 3/5 gallons of blue paint. He will use 7/10 for his room. How much Blue paint will Marcus use for his room?

Question

Marcus has 2 3/5 gallons of blue paint. He will use 7/10 for his room. How much Blue paint will Marcus use for his room? This really confusing so please help me

Answer 1

Answer: 91/50 gallons, or 1.82 gallons. 

 

Explanation:

 

I'll give you some simple rules and steps that should allow you to solve this problems and future ones like it. Overall, in this problem Marcus has a certain amount of paint and he's going to use some amount of it on his room (7/10ths). How much will he use is the question?

 

Step 1: Turn the 2 3/5, ugly looking fraction, into something you can multiply with

 

Here's the trick for this. Worth memorizing. Take the bottom number of the fraction ('5'), multiply it by the number not in the fraction, sitting alone ('2'), and then take the product of those numbers (10 <-- 5x2) and add the top number to it (13 <-- 10+3). 

 

Now take the end result ('13'), and put it over the bottom number in the original fraction, '5'. Your left with 13/5, which is exactly equivalent to 2 3/5. (This process if called turning a mixed fraction into an improper fraction. Worth looking into/practicing further.)

 

Step 2: Multiply the 2 fractions:13/5 x 7/10

 

To multiple them, just multiply the top numbers together and the bottoms numbers together to make a new fraction. So the new fraction is (13x7)/(5x10), or 91/50. In decimal form, it's 1.82 (divide and see on your calculator). 

 

Hope this helps,

Sean