Question

Mr. Johnson's lunch bill is $29.90, which includes a 15% típ

What is the price before tip, b, of Mr. Johnson's lunch?

Answer 1

the answer is 26

Explanation:

Answer 2

price before tip (b) = $26

Explanation:

29.90 is INCLUDING tip, so the real bill, b, would be less.

Now, since 29.90 is including 15% tip, and we let the original bill be "b", we can say:

b INCREASED by 15% gives us 29.90

We need to come up with an equation and solve for b.

15% means 15/100 = 0.15

Now, we can write:

b + 15% of b = 29.90

or

b + 0.15b = 29.90

then

1.15b = 29.90

b = 29.90/1.15

b = 26

So, price before tip (b) = $26