Question

Find the percent of decrease from 340 to 150. Round to the nearest tenth of a percent if necessary.

Answer 1

well, from 340 down to 150, their difference is 190.

now, if we take 340 to be the 100%, what is 190 off of it in percentage?

$\bf \begin{array}{ccll} amount&\%\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ 340&100\\ 190&p \end{array}\implies \cfrac{340}{190}=\cfrac{100}{p}\implies p=\cfrac{190\cdot 100}{340}\implies p\approx 55.88$