Question

A person was appointed to count Rs 2830. During the first 15 minutes he counted At a uniform rate of rupees 100/minute and there after he counted Rs 3 less each minute than the previous minute. Find the time taken to count the money.

Answer 1

Answer:

459.33 minutes

Step-by-step explanation:

It is given that:

• Total money to be counted is Rs 2830
• During the first 15 minutes, he counts at a rate of 100/minute
• After that, he counts Rs 3 less each minute

The total money counted in the first 15 minutes = 15*100 = 1500 Rs.

Therefore, the total money left to be counted = 2830 - 1500 = 1330 Rs.

Since each minute he counts less by 3 Rs, therefore, we have an Arithmetic Sequence with difference 'd' = -3.

The A.S. will be as follows: 1330, 1327, 1324,......,0

With first term 'a' being 1330, and last term 'an' being 0.

$a_n=a+(n-1)d\\0=1330+(n-1)(-3)\\3n-3=1330\\3n=1333\\n=444.333$

Therefore, the total number of minutes = 15+444.33 = 459.33 minutes