Hey, yo, all. How’s the GED math goin’ on? Last time, I talked about problems with percent increase, and now let’s look at percent decrease. It be all about knowin’ what the question’s really askin’. Remember, I said, when it asks what’s the percent increase, what it means is:
What Percent OF the Original amount IS the Difference between the two amounts?
P × O = D
Percent decrease is pretty much the same thing. What percent of the original amount is the difference between the two amounts? Only difference in figuring it out is that the second amount is lower than the first, not higer. No sweat. The percent times the original amount still equals the difference. It’s just a decrease, not an increase. Get it?
Let’s look at it. Here’s a practice problem.
I filled up my car, so it had 15 gallons of gas in the tank. So, I drove out to my uncle’s house and back, and it took $18 in gas at $2 per gallon to fill up the tank. What was the percentage decrease in gas during the trip?
Did I get you with a tough one? More than jus’ one step here. Try to figure it out, then I’ll walk you through it… Continue reading