Question

Estimate a 15% tip on a dinner bill of $89.14 by first rounding the bill amount to the nearest ten dollars. 1

Answer 1

Let:

C = Cost of the dinner

T = Tip

r = Percentage of the tip

`\begin{gathered} C=89 \\ r=0.15 \\ T=C\cdot r \\ T=89\cdot0.15 \\ T=13.35 \end{gathered}`

Answer:

$13.35