The rate of advertisement on a TV channel is directly proportional to the duration of the advertisement. If the rate of an advertisement of 20 seconds is Rs. 1,25,000, then the rate of an advertisement of 25 seconds will be Rs. ________.

Correct option is C

Given:
Rate is directly proportional to duration
20 seconds advertisement costs ₹1,25,00
Duration required = 25 seconds
Formula Used:
If rate ∝ duration, then $$\frac{ \text{Rate}_1 }{ \text{Rate}_2 } = \frac{ \text{Time}_1 }{ \text{Time}_2 }$$​​
Solution:
$$\frac{R_1}{T_1} = \frac{R_2}{T_2}\\\ \\\frac{1,25,000}{20} = \frac{R_2}{25}\\\ \\R_2 = \frac{1,25,000 \times 25}{20}\\\ \\R_2 = 1,56,250\\\ \\$$​​