Question

c) 2.5-1.4 x 1.4 x 1.4 2.5 x 2.5 x (2.5)² + 2.5 x 1.4+ (1.4)²

Answer 1

We will have the following:

$\begin{gathered} \frac{2.5\ast2.5\ast2.5-1.4\ast1.4\ast1.4}{(2.5)^2+2.5\ast1.4+(1.4)^2}=\frac{15.625-2.744}{6.25+3.5+1.96} \\ \\ =1.1 \end{gathered}$

So, the simplification is equal to 1.1.

***Explanation***

$\frac{2.5\operatorname{\ast}2.5\operatorname{\ast}2.5-1.4\operatorname{\ast}1.4\operatorname{\ast}1.4}{(2.5)^2+2.5\operatorname{\ast}1.4+(1.4)^2}$

First, we multiply all the values that are asked to be multiplied, and we also operate all the exponents. [We recall that a value at the power of a number is the number of times the value is multiplied by itself], then we get that:

$\frac{2.5\ast2.5\operatorname{\ast}2.5-1.4\operatorname{\ast}1.4\operatorname{\ast}1.4}{(2.5\ast2.5)+2.5\operatorname{\ast}1.4+(1.4\ast1.4)}=\frac{15.625-2.744}{6.25+3.5+1.96}$

Finally we operate the simpler and lower in the hierarchy of operations expressions: