Question

A quantity decreases from 35 to 30 % decrease A quantity increases from 30 to 35 % increase The price of a Latte dropped from $3.12 to $3 % decrease The cost of Gasoline rose from $3 to $3.12 % increase.

Answer 1

A quantity decreases from 35 to 30 % decrease

`\% decrease= (|30-35|)/(35)*100 =14.29\%`

A quantity increases from 30 to 35 % increase

`\% increase= (|35-30|)/(30)*100 =16.67\%`

The price of a Latte dropped from $3.12 to $3 % decrease

`\% decrease= (|3-3.12|)/(3.12)*100 =3.85\%`

The cost of Gasoline rose from $3 to $3.12 % increase

`\% increase= (|3.12-3|)/(3)*100 =4\%`

Explanation:

For this case we can use the following formula in order to calculate the % of increase or decrease:

`\% = (|Final -Initial|)/(Initial)*100`

Where Final represent the final value and Initial the initial value.

A quantity decreases from 35 to 30 % decrease

`\% decrease= (|30-35|)/(35)*100 =14.29\%`

A quantity increases from 30 to 35 % increase

`\% increase= (|35-30|)/(30)*100 =16.67\%`

The price of a Latte dropped from $3.12 to $3 % decrease

`\% decrease= (|3-3.12|)/(3.12)*100 =3.85\%`

The cost of Gasoline rose from $3 to $3.12 % increase

`\% increase= (|3.12-3|)/(3)*100 =4\%`