Smiths have driven 400 miles which is 5/8 of their trip how much further they have to drive

Question

Smiths have driven 400 miles which 5/8 of their trip. How much further do they have to drive

Answer 1

First, let's translate this into an equation.

 

400 is 5/8 of what number?

 

The missing number in this equation is the total trip miles.

 

400 x 8 is 3200

3200 divided by 5 is 640

 

640 is the total trip miles.  Now we can take 3/8 of the 640 or we can just subtract 400 from 640.

 

640 minus 400 is 240.  Let't check our answer.

 

640 times 3 is 1920.  1920 divided by 8 is 240.

 

How much further do they have to drive?  The have to drive 240 more miles.