Answer: At the end of May, there will be $372.
Explanation:
Since we have given that
On the first day of May, each one save =$0.25
Number of friends = 3
Total save on the first day of May is given by
Similarly,
On the second day of May, each one save =$0.25
Total save on the second day of May is given by
Similarly,
On the third day of May, each one save =$0.25
Total save on the third day of May is given by
This series becomes arithmetic progression,
Here, a = 0.75
d=common difference is given by
Since there are 31 days in the month of May,
So, n=31
We need to calculate the sum of 31 terms to get our answer,
Hence, at the end of May, there will be $372.