Question

if fixed monthly rent for 2000 minutes of voice call is ₹99 and after that ₹50 per minute for each voice call is charged. if Mr. karmakar paid a bill of ₹120, find the value of the voice call.

Answer 1

You can solve this question as
Total bill paid = 120 = 99+ 21
Now, By Unitary method we will calculate the no. of calls in Rs 21.
In 50 rupees, 60 sec. call.
In 21 rupees,
(60/50 )*21= 126/5 sec.
total voice calls = 2000 min 126/5 sec.

Answer 2

total call is 2000 m/s is 12/6