word problem

Question

your favorite cookie recipe calls for 225g of butter, 110g of sugar, 275g of flour and makes 30 cookies. at your local grocery store, flour is sold in 2.5kg bags for $5.99, sugar is sold in 4kg backs for $6.69, and butter is sold in 454g sticks for $3.99. how many cookies can you make if you $100 to spend on supplies?

Answer 1

There might be a more elegant way to do this but as I am unsure what level of math you are in, here is the more rudimentary way to go about it.

 

First, find out how many servings are in a package and how much each serving costs:

Butter: 225g*3.99/454g=$1.98/serving

           454g/225g= 2.01 serving/package

 

Sugar: 110g*6.69/4000g=$0.18g/serving

           4000g/110g=36.36 serving/package

 

Flour: 275g*5.99/2500g=$0.66/serving

         2500g/275g=9.09 serving/package

 

 

Add up the price per servings and see how many times it goes into $100

1.98+0.66+0.18=$2.80/serving

100/2.80=35.7 servings (35 servings because we can't have a fraction of a batch)

 

Now go back and see if this works with the number of servings in a package since we can't buy part of a package at the store:

Butter 35 servings/2.01 servings per pack=17.4 packages (18 package)

          18*3.99=$71.82

Sugar 35 servings/36.36 servings per pack= 0.96 packages (1 package)

          1*6.69=$6.69

Flour 35 servings/9.09 servings per pack= 3.85 packages (4 packages)

        4*5.99=$23.96

 

Is this less than $100?

71.82+6.69+23.96=$102.47

No :(

 

So lets try one less batch of cookies:

Butter 34 servings/2.01 servings per pack= 16.92 packages (17 packages)
17*3.99=$67.83
Sugar 34 servings/36.36 servings per pack= 0.94 packages (1 package)
1*6.69=$6.69
Flour 34 servings/9.09 servings per pack= 3.74 packages (4 packages)
4*5.99=$23.96

 

Is this less than $100?
67.83+6.69+23.96=$98.48

 

Yes! So back to the original question: how many cookies can you make for $100?

30 cookies/batch * 34 batches= 1020 cookies

 

Let me know if you have any further questions!