A Protein bar has 33% of the protein you need daily. You must get the remaining 12 grams of protein from other sources.

Question

A Protein bar has 33% of the protein you need daily. You must get the remaining 12 grams of protein from other sources. Approximately how many grams of protein do you need daily?

Answer 1

Let's let T represent the total protein we need each day.

 

STEP 1:  

 

We have two comments about Total protein needed:

 

A:  12 grams

B:  the remaining protein other than the Protein bar.  Since the Protein bar gives us 33% of our daily requirement, the rest has to be 100% - 33% = 67% of our total protein needs.  (change the % to a decimal:  67% = .67)  

 

Translate "67% of our total protein" into an algebraic expression:  .67T    

 

STEP 2: 

 

We can us our two definitions for the total amount:   12 = .67T

 

Solve for T:   12/.67 = T  

 

Calculating the division, we get 17.9  = T 

 

This is about 18 grams of protein we need each day.

 

CHECK:

 

Does this answer make sense?   33% is about 1/3.   1/3 of 18 = 18/3 = 6 grams.  So the remainder is 18 - 6 = 12 grams.

 

This fits the original question.

 

Let me know if you have any questions.

Ms. Horvath