Question

By evaluating $\frac{{2.8}^3\times {1.2}^2}{0.56+3.78}$, closest estimate answer is:

• A. $7$
• B. $70$
• C. $0.7$
• D. None of these

Answer 1

Answer: (A)

$7$

We need to evaluate $\frac{{2.8}^3\times {1.2}^2}{0.56+3.78}$

$\Rightarrow$ $\frac{3^3\times 1.44}{4.34}$ $[\because 2.8\approx 3]$

$\Rightarrow$ $\frac{27\times 1}{4}$ $[\because 1.44\approx 1\text{and}4.34\approx 4]$

$\Rightarrow$ $6.75\approx 7.$

Therefore, $\frac{{2.8}^3\times {1.2}^2}{0.56+3.78}=7$