# What is 3(36-:9)+2(80-60)-3*4?

Sep 16, 2016

3(36-:9)+2(80-60)-3*4="color(blue)(40)

#### Explanation:

This question is designed to apply the order of operations, given as PEMDAS.

Simplify $3 \left(36 \div 9\right) + 2 \left(80 - 60\right) - 3 \cdot 4$

Simplify $- 3 \cdot 4$ to $- 12$.

$3 \left(36 \div 9\right) + 2 \left(80 - 60\right) - 12$

Simplify the terms inside each pair of parentheses.

$3 \left(4\right) + 2 \left(20\right) - 12$

Multiply the term inside each pair of parentheses by the term outside.

$12 + 40 - 12$

Simplify.

$40$

Sep 16, 2016

$40$

#### Explanation:

The most important starting point in a calculation involving different operations is to COUNT the number of terms first.

Each term will simplify to a single answer and these are added or subtracted in the last line.

It is possible to work in separate terms in the same line of working and in this way more than one operation can be done in a line,

Within each term ,
$\rightarrow$ brackets are done first,
$\rightarrow$ then powers and roots, and
$\rightarrow$ lastly multiplication and division.

ONLY then does addition and subtraction happen, from left to right.

$\textcolor{b l u e}{3 \left(36 \div 9\right)} \textcolor{red}{+ 2 \left(80 - 60\right)} \textcolor{o l i v e}{- 3 \times 4} \text{ } \leftarrow$ has 3 terms

=$\textcolor{b l u e}{3 \left(4\right)} \textcolor{red}{+ 2 \left(20\right)} \textcolor{o l i v e}{- 12}$

=$\textcolor{b l u e}{12} \textcolor{red}{+ 40} \textcolor{o l i v e}{- 12} \text{ } \leftarrow$+12-12 are additive inverses.

=$40$