If four times a number, added to 3 is divided by the number plus 8, the result is seven halves.

Question

 Find the number

Answer 1

Hi Emily,

 

Let's translate the English into math:

 

Let X = the number

 

Four times a number--> 4X

 

added to 3--> 4X + 3

 

is divided by the number plus 8--> (4X + 3)/(X + 8)

 

the result is seven halves--> (4X + 3)/(X + 8) = 7/2

 

Cross multiply--> 7X + 56 = 8X + 6

 

Subtract 7X from both sides and subtract 6 from both sides--> 50 = X

 

Plug this number back into the question to make sure it works.  Remember that 7/2 is the same as 3 1/2 which is the same as 3.5.

 

Have fun.

 

Dan