Question

2. Yasmeen saves Rs. 32 during the first month, Rs. 36 in the second month and Rs.40 in the third month. If she continues to save in this manner, in how many months she will save Rs. 2000, which she has intended to give for the college fee ofher maid 's daughter. What value is reflected here.

Answer 1

30 is answer
its easy .i request you to try yourself

Answer 2

Answer:

25 months

Step-by-step explanation:

Given : Yasmeen saves Rs. 32 during the first month, Rs. 36 in the second month and Rs.40 in the third month.

To Find: If she continues to save in this manner, in how many months she will save Rs. 2000, which she has intended to give for the college fee ofher maid 's daughter.

Solution:

First month saving = rs.32

Second month saving = Rs.36

Third month saving = Rs.40

It forms AP

32,36,40,....

a = first term = 32

d = common difference = $36-32=40-36=4$

Now we are supposed to find in how many months she will save Rs. 2000

So, Formula  : $S_n=\frac{n}{2}(2a+(n-1)d)$

$2000=\frac{n}{2}(2(32)+(n-1)4)$

$4000=n(64+4n-4)$

$4000=n(60+4n)$

$4000=60n+4n^2$

$1000=15n+n^2$

$15n+n^2-1000=0$

$n^2+40n-25n-1000=0$

$n(n+40)-25(n+40)=0$

$(n+40)(n-25)=0$

$n=-40,25$

Since number of months cannot be negative

So, she will save Rs. 2000 in 25 months