Answer:
10000 unit cost
Step-by-step explanation:
Given amount after 2 years: 12100 unit cost
Amount after 3 years: 13310 unit cost
Remember:
- The amount after 2 years always becomes the principal for the 3rd year,i.e.here,the principal for third year equals 12100 unit cost
For the time being of 3rd year,
- Amount(3rd) = Principal (3rd)*(1 + r/100)^n
Here n = time being = 1 year since the amount is specified only for one year(3rd year)
- 13310 = 12100(1 + r/100)
- 13310/12100 = 1 + r/100
- 11/10 - 1 = r/100
- 1/10 = r/100
- r = 10%
The original sum = ?
Original sum = P ( Assume)
Here for second year
- A = P(1+r/100)^n (n = 2)
- 12100 = P(1 + 10/100)²
- 12100 = P( 11/10)²
- (12100 * 10*10)/121 = P (Divide both sides by (10/11)²)
- P = 100*10*10 = 10000 unit cost
