Step 1: Interpret the problem.
Given the heart rate dropped by 30%, we know:
100% – 30% = 70%
The remaining heart rate percent is 70%.
Step 2: Turn the percent into a decimal.
To turn a percentage into a decimal, we divide by 100, which is the same as moving the decimal point two spaces to the left.
70% = 70.%
70.% ÷ 100 = .70
.70 = .7
Step 3: Determine the original heart rate.
Current Heart Rate ÷ Decimal = Original Heart Rate
63 ÷ .7 = 90
The patient’s heart rate before the drop was 90 beats per minute.