Answer:
The number of years in which saving gets double is 8 years .
Step-by-step explanation:
Given as :
The principal amount saved into the account = p = $8,000
The rate of interest applied = r = 9%
The Amount gets double in n years = $A
Or, $A = 2 × p = $8,000 × 2 = $16,000
Let the number of years in which saving gets double = n years
Now,<u> From Compound Interest method</u>
Amount = Principal ×
Or, 2 × p = p ×
Or, $16,000 = $8,000 ×
Or, =
Or, 2 =
Now, Taking Log both side
2 =
Or, 0.3010 = n × 1.09
Or, 0.3010 = n × 0.0374
∴ n =
I.e n = 8.04 ≈ 8
So, The number of years = n = 8
Hence, The number of years in which saving gets double is 8 years . Answer