+299 Identify the percent of change as an increase or a decrease then find the percent of change. Round to the nearest tenth of a percent if needed
question #1 120 pounds to 180
question #2 10ft to 8ft
+9466 1.
180 is bigger than 120 so this is an increase.
120 increased by what percent of 120 is 180 ?
Let x be the percent of increase.
120 + 120x = 180
120x = 60
x = 60/120 = 0.5 = 50/100 = 50%
120 increased by 50% of 120 is 180 .
2.
8 is smaller than 10 so this is a decrease.
10 decreased by what percent of 10 is 8 ?
10 - 10x = 8
-10x = -2
x = -2 / -10 = 20 / 100 = 20%
10 decreased by 20% of 10 is 8 .
+128474 Thanks for that good answer, hectictar.......here's another way to do this......
We can actually use the same "formula" to figure both of these
% increase / decrease = ( l New Value - Old Value l / Old Value x 100 ) %
So...for the first one we have
( l 180 - 120 l / 120 x 100) % =
( l 60 l / 120 x 100 ) % =
( 60 / 120 x 100 ) % =
( 1 / 2 x 100 ) % =
50% increase
For the second one, we have
( l 8 - 10 l / 10 x 100 ) % =
( l -2 l / 10 x 100 ) % =
( 2 / 10 x 100 ) % =
( 1 / 5 x 100 ) % =
20% decrease
