tian makes his own pizza dough. he uses 2 packages of yeast for every 3 cups of flower. he needs 5 cups of flower to make enough pizza...

Question

tian makes his own pizza dough. he uses 2 packages (p) of yeast for every 3 cups (c)of flour. he needs 5 c flour to make enough pizza for his family. how many packages of yeast does he need?

Round answer to nearest tenth

Answer 1

This is a simple proportion problem that is most easily solved using cross multiplication.

 

2 = p

3    5

 

3p = 2(5)

3p = 10

p = 3.3

Answer 2

This question can be solved using ratios. 

You can use the following equation:

2/3=p/5 

2 represents packages of yeast

3 represents cups of flour

p represents the unknown number of packages of yeast

5 represents cups of flour 

 

To solve you are going to move the variable to a side all by itself. The right side reads p divided by 5. To move the 5 to the other side you are going to perform the inverse operation and that is to multiply by 5. That leaves you with:

 

(2/3)*5=p   (* represents the multiplication function)

 

This is the same as (2/3)*(5/1) because any number is the same when above a 1

Then you can multiply across so it is:

 

 

(2*5)/(3*1)=p

 

(10)/(3)=p

using long division or a calculator you get 3 and 1/3 or 3.3333333333. To the nearest tenth this is 3.3 packages of yeast