Question

estimate:
$19\frac{8}{9} - 10\frac{1}{8} = \underline{\quad\quad}$
a 19
b 21
c 10
d 8

Explanation:

Step1: Round mixed numbers

Round $19\frac{8}{9}$ to 20, since $\frac{8}{9} \approx 1$. Round $10\frac{1}{8}$ to 10, since $\frac{1}{8} \approx 0$.

Step2: Subtract rounded values

$20 - 10 = 10$

Answer:

C. 10