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# Percent of change: word problems

At a supermarket, a certain item has increased from 75 cents per pound to 81 cents per pound. What is the percent increase in the cost of the item?

There was an 8% increase in the cost of the item.

If the price of gas increases from $1.00 per gallon to$1.21 per gallon, what is the percent of increase?

The percent of increase is 21%.

Howard bought a guitar for $100 and sold it for$127. What percent profit did Howard make on the guitar?

The percent of profit was %