Respuesta :

Answer:

considering it was simple interest,

We have the formula:

I = PRT ÷ 100

where,

  • I = Interest
  • P = principal
  • T = time (in years)
  • R = rate

for the first part of the question,

  • P = Rs. 2160
  • R = 20
  • T = 4

Thus, I = (2160 × 20 × 4)÷ 100

I = Rs. 1728

Now, for the second part,

  • P = Rs. 1800
  • I = 1728
  • R = 12

T = 100×I÷PR

T = 100 × 1728÷(1800 × 12)

T = 8 Years