A man saves rs 32 during the first year, rs 36 in the second year and in this way he increase his savings by rs 4 every year. find in what time his savings will be rs 200.
Answers
Answered by
7
Answer:
Given, A man saved in first year, a = 32
A man saved in second year, a2 = 36
Increase saving, d = 4
In n years his saving will be 200, Sn = 200
We know,
Sn =[2a + (n – 1) d]
200 =[2(32) + (n – 1) 4]
400 = n [64 + 4n – 4]
400 = n [60 + 4n]
400 = 4n [15 + n]
100 = 15n + n2
n2 + 15n – 100 = 0
n2 + 20n – 5n – 100 = 0
n (n + 20) – 5 (n + 20) = 0
(n – 5) (n + 20) = 0
Here, n – 5 = 0, n = 5
n + 20 = 0, n = -20
The term can never be negative. So, we consider n = 5
Hence, in 5 years his saving will be Rs. 200
Answered by
2
Answer:
use formula
an = a +( n-1)d
a =32
d=4
200=32+(n-1)4
168=(n-1)4
n-1=168/4
n-1=42
n=43
In 43 years....
please mark my answer as brainliest ,friend....
Similar questions