Matthew has 3 1/4 gallons of lemonade. He sells 4/8 of the lemonade. How many gallons of lemonade does Matthew have left

Answer 1

Question: Matthew has 3 1/4 gallons of lemonade. He sells 4/8 of the lemonade. How many gallons of lemonade does Matthew have left?

Answer: I'm glad to be answering this question in the middle of a hot summer.

Once Matthew sells 4/8 of the lemonade, we have lost that lemonade. This is a subtraction problem.

Let's do 3 1/4 minus 4/8. If I can re-write 1/4 with the same denominator as (4/8), it will be easier to do this problem. The common denominator between 1/4 and 4/8 is 8. We only need to re-write 1/4. Multiply numerator and denominator by 2, and so 1 x 2 =2 and 2 x 4 = 8. (1/4) is equivalent to (2/8).

We can now write the subtraction problem as 3 2/8 - 4/8. If we try to subtract 4/8, we'll see that we'll have 3 by subtracting 2/8, and then we still need to take away another 2/8. We'll get 2 6/8 by doing this. We get here if we think of 3 as 2 8/8 (this mixed number represents 2 + 8/8, or 2 + 1, which is 3).

We have 2 6/8. We can reduce 6/8 by dividing top and bottom by 2. That gives us 3/4.

Matthew has 2 3/4 gallons of lemonade left.