Question

an NA A mathematician simplifies the expression mentally. 4-6.1+2 (7.9+3) What is the best estimate of the value of the expression? BE 25 O 20 O 17 10 * Calculator

Answer 1

Simplify the expression 4-6.1+2(7.9+3) by using the BODMAS rule.

$\begin{gathered} 4-6.1+2(7.9+3)=4-6.1+2(10.9) \\ =4-6.1+21.8 \\ =19.7 \\ \approx20 \end{gathered}$

Thus estimated value of expression is 20.