Question

A student saves is ₹5 in each week.what is the
the total amount of his savings after
15 weeks???​

Answer 1

Answer:

Saving made in first week=5

Saving made in second week=5+1.75=6.75

Saving made in third week=6.76+1.75=8.50

So, the series is 5,7.75,8.50,...

Since difference is same, it is an A.P

Common difference=d=1.5

Given:In n

th

week, her savings become Rs.20.75

So, a

n

=20.75

Also,a=5,d=1.75

Using a

n

=a+

left(n−1

right)d

Rightarrow20.75=5+

left(n−1

right)

times1.75

Rightarrow15.75=

left(n−1

right)

times1.75

Rightarrown−1=

dfrac15.751.75=9

Rightarrown−1=9

thereforen=10

Hence, in 10

th

week, her weekly savings become Rs.20.75

Answer 2

Answer:

75 rupees saves by a student