If the cost of a long-distance phone call is C taka for the first minute and (2/3)C taka for each additional three minutes, what is the cost, in taka, of a 10 minute call of this type?

If the cost of a long-distance phone call is C taka for the first minute and (2/3)C taka for each additional three minutes, what is the cost, in taka, of a 10 minute call of this type?

A (5C/3)

B 6C

C 3C

D 7C

Solution

Correct Answer: Option C

first minute cost =c then, every 3 minute cost = C X (2/3) = (2C/3)

∴ total cost = 10 minute
= (2C/3) + (2C/3) + (2C/3) + C
= (6C/3) + C
= 9C/3
= 3C