Answer
Estimated answer = 14
Exact answer = $13\frac{1}{2}$
Work Step by Step
$12\frac{4}{5}$ + $\frac{7}{10}$
Estimation:
$12\frac{4}{5} \approx 13$
$\frac{7}{10} \approx 1$
Therefore
$12\frac{4}{5}$ + $\frac{7}{10}$ $\approx$ 13 + 1 = 14
Exact Calculation:
$12\frac{4}{5}$ + $\frac{7}{10}$
= $12\frac{4\times2}{5\times2}$ + $\frac{7}{10}$
(10 is the least common denominator)
= $12\frac{8}{10}$ + $\frac{7}{10}$
= $12$ + $\frac{8}{10}$ + $\frac{7}{10}$
(taking whole part separately and fractional part separately)
= $12$ + $\frac{8 + 7}{10}$
= $12$ + $\frac{15}{10}$
= $12$ + $\frac{10 + 5}{10}$
= $12$ + $\frac{10}{10} + \frac{5}{10} $
= 12 + 1 + $\frac{1}{2}$
= $13\frac{1}{2}$
The estimate was 14, so the exact answer of $13\frac{1}{2}$
is reasonable.
