Correct Answer - Option 1 : 9 years
FORMULA USED:
Simple Interest = PRT/100
Where, P = principle, R = Rate of interest, T = time period
CALCULATION:
According to the question
(10000 × 4 × T)/100 = (12000 × 6 × 5)/100
⇒ T = 360000/40000 = 9
∴ The required time = 9 years