# Fractional Parts

If you spend one-fourth of a dollar, how much is left?

First divide the dollar into four equal pieces (the denominator -- bottom number -- tells how many equal pieces are in each whole thing). 100 ÷ 4 = 25. That's the amount used.   What was the question?   How much of the dollar is left?

You can set-up and solve this type of question as a proportion: Use cross-products to solve: 3 times 100 = 4 times (the missing part)

 3 times 100 = 4 times the amount left 300 = 4 times the amount left 300/4 = 4/4 times the amount left 75 (cents) = the amount left

Notice that the answer will be for whatever question you asked --the set-up can save you an extra step later (or save you from forgetting that there was a second step).

You fold one-third of sixty napkins.   How many are left?  Jack's rent is two-fifths of his income.   If he earns \$1500, how much is his rent? PRACTICE QUESTIONS:

 1) Tom broke one-sixth of a dozen eggs. How many eggs are not broken? Check your answer 1 out of every 6 eggs ARE broken 5 out of every 6 are UNBROKEN 5/6 = ?/12 5 x 12 = 6 x ? 60 = 6 times the unbroken eggs 60 ÷ 6 = 10 10 eggs are NOT broken. 2) Kim ate one-fourth of sixty mints.   How many mints are left? Check your answer 1 out of every 4 mints were eaten 3 out of EVERY 4 mints are left 3/4 = ?/60 3 x 60 = 4 x ? 180 = 4 times the uneaten mints 180 ÷ 4 = 45 45 mints are left. 3) Pam painted three-fourths of the tiles.   How many of the 80 tiles are painted? Check your answer 3 out of every 4 tiles ARE painted 3/4 = ?/80 3 x 80 = 4 x ? 240 = 4 times the painted tiles 240 ÷ 4 = painted tiles 60 tiles are painted 4) Dale sold one-eighth of the books.   How many of the 40 books are left? Check your answer 1 out of every 8 have been sold 7 out of EVERY 8 books are left 7/8 = ?/40 7 x 40 = 8 x ? 280 = 8 times the unsold books 35 books are left

 ANSWERS: 1)   10 eggs are UNBROKEN     2)   45 are left     3)   60 are painted     4)   35 are left