Question

Change the following phrase into an algebraic equation: Kai's heart beats at 75 beats per minute for a certain number of minutes. If the heart beats a total of 225 beats, how minutes did it beat for?

a) 75x = 225
b) 225x = 75
c) 75 + 225 = x
d) 75 - 225 = x

Answer 1

The correct algebraic equation for the given situation is option (a) 75x = 225, which means that Kai's heart beats for 3 minutes to reach a total of 225 beats.

Step-by-step explanation:

To change the phrase into an algebraic equation, we need to set up an equation that represents the given situation. Kai's heart beats at 75 beats per minute, and the total number of beats is 225. Let x represent the number of minutes Kai's heart beats for. Since the heart rate is 75 beats per minute, we multiply this rate by the number of minutes to find the total number of beats:

75x = 225

This equation can be solved by dividing both sides by 75 to find the value of x.

75x / 75 = 225 / 75

x = 3

Therefore, Kai's heart beat for 3 minutes to reach a total of 225 beats. Hence, option (a) 75x = 225 is the correct algebraic equation that represents the situation.