MULTIPLYING RATIONAL NUMBERS WORD PROBLEMS

Problem 1 : 

A student can eat 1/8 of a pizza. If there are 40 students in David's class, how many pizzas does David need ?

Solution :

To find how many pizzas that David needs, we have to multiply 40 and 1/8. 

Step 1 : Multiply 40 by 1/8

40 x 1/8  

Step 2 : Simplify

5 x 1/1

Step 3 : Multiply 

5 x 1/1  =  5    

So, David needs 5 pizzas. 

Problem 2 : 

There are 450 students in school. If 4/9 th of the students are boys, find the number girls in the school. 

Solution :

If 4/9 of the students are boys, then 5/9 th of the students are girls. Because 9 - 4  =  5.

To find number of girls, we have to multiply 450 by 5/9. 

Step 1 : Multiply 450 by 5/9

450 x 5/9     

Step 2 : Simplify

50 x 5/1

Step 3 : Multiply 

50 x 5/1  =  250    

So, there are 250 girls in the school. 

Problem 3 : 

The science teacher is filling her new fish aquarium. The aquarium holds 40 gallons. If she fills the aquarium 4/5 of the way full, how many gallons will she need?

Solution :

If 4/5 of the aquarium is filled, then 1/5 th of the aquarium to be filled to make it full. Because 5 - 4  =  1.

To find number of gallons, we have to multiply 40 by 1/5. 

Step 1 : Multiply 40 by 1/5

40 x 1/5     

Step 2 : Simplify

8 x 1/1

Step 3 : Multiply 

8 x 1/1  =  8    

So, the science teacher needs 8 gallons to make the aquarium full. 

Problem 4 : 

A baker needs to make 8 batches of cookies for a party. If each batch requires 2 3/4 cups of flour, how many cups will he need ?

Solution :

To find number of cups needed, we have to multiply 8 by 2 3/4. 

Step 1 : Multiply 8 by 2 3/4

8 x 2 3/4     

Step 2 : Simplify

8 x 11/4  =  2 x 11/1

Step 3 : Multiply 

2 x 11/1  =  22    

So, the baker needs 22 cups of flour to make 8 batches of cookies. 

Kindly mail your feedback to v4formath@gmail.com

We always appreciate your feedback.