Beth and Billy are biking to their friend Bernie's house. After 1 mile, Beth and Billy have traveled 4/5 of the total distance to Bernie's house. How much farther do Beth and Billy have to go in order to arrive at Bernie's?

Answer: they need to cover 0.25 miles.

Step-by-step explanation:

Let x represent the total distance that they have to cover to get to Bernie's house.

Beth and Billy are biking to their friend Bernie's house and after 1 mile, Beth and Billy have traveled 4/5 of the total distance to Bernie's house. This would be expressed as

4.5 * x = 1

4x/5 = 1

Multiplying the left hand side and the right hand side of the equation by 5, it becomes

4x/5 * 5 = 1 * 5

4x = 5

Dividing the left hand side and the right hand side of the equation by 4, it becomes

4x/4 = 5/4

x = 1.25

Therefore, the remaining distance that they need to cover to arrive at Bernie's is

1.25 - 1 = 0.25 miles