When a grizzly bear hibernates, its heart rate drops to 101010 beats per minute, which is 20\%20%20, percent of its normal value. What is a grizzly bear's normal heart rate when not hibernating?

We know that the rate of $10$10 beats per minute is equal to $20\%$20, percent of the normal rate. We need to find out the normal $(100\%)$left parenthesis, 100, percent, right parenthesis number of beats per minute a grizzly bear has when not hibernating.

Since we already know the value for $20\%$20, percent, we can just multiply by $5$5 to see how many heart beats equal $100\%$100, percent.

Percent	$20\%$20, percent	$\stackrel{\times 5}\rightarrow$right arrow, start superscript, times, 5, end superscript	$100\%$100, percent
Heart beats	$10$10	$\stackrel{\times 5}\rightarrow$right arrow, start superscript, times, 5, end superscript	$50$50

The grizzly bear's usual heart rate is $50$50 beats per minute.