5th grade math (word problems)
posted by Alex .
Problem: A receipe for 4 dozen cookies requires 1 1/2 cups of flour. How much flour is needed for 1 dozen?
work: 4 divided by 1 1/2 = 4/1 x 3/2 =
4/1 x 2/3 = 8/3 cups of flour
Can you explain why i don't need to change 4 dozen to 48 and then divide by 1 1/2?

It's simpler to work with dozens than with 48. (Too many numbers)
You know you'll only need one fourth as much flour for one dozen cookies.
Let's work it this way. Cross multiply and solve for x.
4 / (1 1/2) = 1 / x
4x = 1 1/2
x = (1 1/2) / 4
x = 3/2 * 1/4
x = 3/8 cup 
thanks!

You're welcome.

27
Respond to this Question
Similar Questions

algebra
If you made 3 1/2 dozen cookies and used 7 7/8 cups of flour, how much flour do you use for each dozen 
Math Help
A recipe calls for 3 cups of flour to make 3 dozen cookies. Use the proportion to calculate how much flour is needed to make 9 dozen cookies. 3 cups/3 dozen= x cups/9 dozen A. 6 cups B. 3.5 cups C. 9 cups D. 12 cups Is the answer C? 
math
A recipe calls for 2 cups of flour to make 2 dozen cookies. Use the proportion to calculate how much flour is needed to make 6 dozen cookies. 2 cups/2 dozen= x cups/6 dozen A. 2 cups B. 4 cups C. 6 cups D. 12 cups Is the answer C? 
Math
A cookie recipe calls for 2/3 of a cup of flour and makes half a dozen cookies. How many cookies can you make if you have 9 cups of flour and want to use it all? 
prealgebra
A recipe for chocolate chip cookies calls for 1 cup sugar and 1 1/4 cups of flour. If the recipe makes 3 1/2 dozen cookies, how many cups of flour will be needed to make 12 dozen cookies? 
Math
a recipe for 2 dozen cookies calls for 1 1/3 cups of flour.how much for would be needed to make five dozen cookies? 
Math
A recipe for 2 1/2 dozen cookies calls for 1 7/8 cups of flour. How many cups of flour are needed to make 1 1/3 dozen cookies? 
Math
A recipe for cookies calls for 7 and one half 7 1 2 cups of flour. If the recipe is for 22 dozen cookies, how much flour is needed for 1313 dozen cookies? 
Math
A recipe for cookies calls for 7 1/2 cups of flour. If the recipe is for 2 dozen cookies, how much flour is needed for 13 dozen cookies? 
Math
A recipe for 2 dozen cookies calls for 1 1/3 cups of flour how much flour would be needed to make 5 dozen cookies