(b)If Soha’s heart beats 72 times in one minute, how many times does it beat in one hour? •Now find out how many times it beats in one day. •Count your own heart beats to find out how many times your heart beats in one week.
Before we proceed with the question, let us first understand the concept of unitary method. Unitary method is a method for solving a problem by first finding the value of a single unit and then finding the necessary value by multiplying it with the single unit value. So, according to the question, Soha’s heart beats 72 times in one minute. So, in the next minute her heart will again beat for 72 times, and then again in the next minute for 72 times and so on. Now, we know that there are 60 minutes in one hour. So if we have to count the heart beats of Soha in one hour, we will add 72 heart beats per minute for 60 times. So, in 60 minutes, her heart beats will be, 72+ 72+ 72+ 72+ ………… 60 times So, we can write this as 72 multiplied with 60 instead of adding 72 for 60 times. So, Soha's heart beats in 60 minutes or one hour = 72×60=4320. Therefore, we get that Soha’s heart beats 4320 times in one hour.
