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Real-Life Math -- Solution

Today, you're trying to determine what the percentage decrease over last year is. Last year, there were 14 avalanches from November through May. This year, during the same period, there have only been 13.

To determine the percentage decrease, you must subtract the number of this year's avalanches from the number of last year's avalanches.

Last year: 14
This year: 13

14 - 13 = 1

Then divide the difference by the number of avalanches that occurred last year and multiply by 100.

1 / 14 x 100 = 7.14

Round that to the nearest whole number. Your answer is 7 percent. There were 7 percent fewer avalanches this year than there were last year.

"On the research side, there are more intricate mathematical models," says Mark Klassen. He is an avalanche technician. "But on the forecasting side, most of the math that we use is simple addition, subtraction, multiplication and division."