# Thread: percent increase and decrease

1. ## percent increase and decrease

Help, I am not sure how to find the percent of increase in a problem or even the percent of decrease. My parents have no idea either!!!

Examples: The sales of HiTop sneakers rose from $4billion to$4.4 billion. What is the percent of increase?

One week, a certain stock market index went down from 1,863 to 1,677. What was the percent of decrease?

Find the percent of chan $20,200 to$17,350.

2. Originally Posted by cckrr4025
Help, I am not sure how to find the percent of increase in a problem or even the percent of decrease. My parents have no idea either!!!

Examples: The sales of HiTop sneakers rose from $4billion to$4.4 billion. What is the percent of increase?

One week, a certain stock market index went down from 1,863 to 1,677. What was the percent of decrease?

Find the percent of chan $20,200 to$17,350.
$\displaystyle \text{percentage change} = \frac{\text{New} -\text{Original}}{\text{Original}} \times 100$

0.1%
-0.099%
-0.141%

3. Originally Posted by cckrr4025
Help, I am not sure how to find the percent of increase in a problem or even the percent of decrease. My parents have no idea either!!!

Examples: The sales of HiTop sneakers rose from $4billion to$4.4 billion. What is the percent of increase?
first you need to know how much it increased

$$\displaystyle 4.4B \displaystyle -$$\displaystyle 4$B =$$\displaystyle 0.4$B

it increased by $0.4 B B(original price)=$4 B
P(amount increased)= $0.4 B R(percent increased)=?$\displaystyle R=\frac{0.4}{4}$in billions R=1% you can check it by$\displaystyle B=\frac{P}{R}$One week, a certain stock market index went down from 1,863 to 1,677. What was the percent of decrease? Find the percent of chan$20,200 to \$17,350.
find first how much it decreased then use the formula