Question

A road in Durham is lengthened to 21 miles, which represents a 5% increase. What was the original length of the road?

Answer 1

The original length of the road was 20 miles.

Explanation:

Let x be the original length of the road in miles.

After being lengthened, the road is 21 miles long, which represents a 5% increase from the original length.

So we can set up an equation to solve for x:

x + 0.05x = 21

Combining like terms:

1.05x = 21

Dividing both sides by 1.05:

x = 20