# How do you use order of operations to simplify #1/7 -: (1/7)^2 - 3/343#?

##### 2 Answers

#### Explanation:

Follow the order of operations set out in the acronym PEMDAS

{P-parenthesis (brackets) ,E- exponents (powers), M-multiplication, D-division, A- addition and S- subtraction]

#rArr1/7÷(1/7)^2-3/343#

#=1/7÷(1/7xx1/7)-3/343#

#=1/7÷1/49-3/343larrcolor(red)" bracket/exponent"# [Change division to multiplication and turn dividing fraction upside down.]

#rArr(1/cancel(7)^1xxcancel(49)^7/1)-3/343larrcolor(red)" division"#

#"Finally " 7-3/343# Change 7 into a fraction with a denominator of 343

#"that is "7/1xx343/343=2401/343#

#rArr2401/343-3/243=2398/343larrcolor(red)" subtraction"#

#### Explanation:

In an expression which has different operations, there is a specific order in which they have to be done.

Identify the number of TERMS first. Each term is treated separately and simplified to a single answer.

These are added or subtracted only in the last line.

Within each term, the order to be followed is:

- brackets,
- followed by powers and roots,
- finally multiplication and division

In this case there are two terms. Simplify each separately.