Karun borrowed ₹12,000 from Varun and ₹15,000 from Tarun, each for two years at the same rate of simple interest per annum. If he paid an interest of ₹1,680 to Varun at the end of 2 years, then what is the interest that Karun paid to Tarun at the end of the 2 year period?

Karun borrowed ₹12,000 from Varun. If he paid an interest of ₹1,680 to Varun at the end of 2 years.

$$interest=\frac{principal\ amount\times\ rate\ of\ interest\times\ time}{100}$$

$$1680=\frac{12000\times\ rate\ of\ interest\times\ 2}{100}$$

$$1680= 240\times\ rate\ of\ interest$$

rate of interest = 7%

interest that Karun paid to Tarun at the end of the 2 year period = $$\frac{principal\ amount\times\ rate\ of\ interest\times\ time}{100}$$

= $$\frac{15000\times7\times2}{100}$$

= $$150\times14$$

= 2,100