Answer
estimate - 32
exact - 31$\frac{43}{80}$
Work Step by Step
12$\frac{3}{5}$ + 8$\frac{5}{8}$ + 10$\frac{5}{16}$
Estimate : 12$\frac{3}{5}$ round to 13
8$\frac{5}{8}$ round to 9
10$\frac{5}{16}$ round to 10
So add 13+ 9 + 10= 32 is the estimate answer
Exact : 12$\frac{3}{5}$ + 8$\frac{5}{8}$ + 10$\frac{5}{16}$
The least common multiple of 5, 8 and 16 is 80. Rewrite all the fractions as fractions with a least common denominator of 80.
Rewrite as like fraction
12$\frac{3}{5}$ + 8$\frac{5}{8}$ + 10$\frac{5}{16}$= 12$\frac{48}{80}$ + 8$\frac{50}{80}$ + 10$\frac{25}{80}$
Add : 12$\frac{48}{80}$ + 8$\frac{50}{80}$ + 10$\frac{25}{80}$
Sum of the whole number is 30 and sum of the fraction is $\frac{123}{80}$
= 30$\frac{123}{80}$
The improper fraction $\frac{123}{80}$ is in lowest terms convert it into mixed fraction 1$\frac{43}{80}$, so the simplified sum is
30$\frac{123}{80}$ = 30 + 1$\frac{43}{80}$ = 31$\frac{43}{80}$
The estimate was 32, so the exact answer of 31$\frac{43}{80}$ is reasonable
