Question

Estimate

Answer 1

A. about 84

B. about 70

C. about 98

D. about 78

Answer 2

@Data_LG2

Answer 3

Hm.. estimating.. ok
\[
13.96 \cdot 6.2 \approx 14 \cdot6.2 \\
14\cdot 6.2 = 14 \cdot (6 + \frac{1}{5}) = 14 \cdot 6 + \frac{14}{5} = (60 + 24) + \frac{14}{5} = \\
= 84 + \frac{14}{5} \approx 84 + \frac{15}{5} \\
84 + \frac{15}{5} = 84 + 3 = 87\\
13.96 \cdot 6.2 \approx 87
\]
This is terrible estimation. alot of rounding, but we get that's it's closest to A, which is about 84. (also notice I rounded up, so we know for sure it's actually less than 87)

Answer 4

What they did btw is even worse estimation:
\[
13.96 \cdot 6.2 \approx 14 \cdot 6 \\
14 \cdot 6 = 10 \cdot 6 + 4\cdot 6 = 60 + 24 = 84
\]
easier to calculate.. but worse.

Answer 5

oh okay, thank u so much!