Finding the percent change given two values
Given a before and an after, find the percent. The only thing to get right is which number goes on the bottom.
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ALEKS randomizes the numbers each attempt, but the question shape stays the same. Here are three example versions you might see.
A cup of coffee went from $2.20 to $2.45.
What is the percent increase? Round to the nearest hundredth. Type just the number.
A shop’s daily takings fell from $340 to $289.
What is the percent decrease? Type just the number.
A part’s price rose from $64 to $80.
What is the percent increase? Type just the number.
A monthly subscription rose from $18.50 to $21.35.
What is the percent increase?
Find the change
Divide by the original
Make it a percent
The denominator is the whole question
Divide by the new price instead and you get 13.35%, which is wrong but plausible enough that nothing looks amiss.
Remember it this way: a percent change answers “how big was the change compared to what I had?” What you had is the old value. It goes on the bottom, every time.