Question

(2) An international call to a certain country costs Rs. 7

Answer 1

Answer:

$y = 43$

Step-by-step explanation:

Given

$First\ Minute = 7$

$Additional\ Minutes = 4$ per minute

Required

Determine the cost of a 10 minutes call

First, we need to determine the expression for the call charges.

Let:

• x = minutes

• y = charges

The relationship between x and y is:

$y = First\ Minute + Additional\ Minutes(Number\ of\ minutes\ - 1)$

i.e.

$y = 7 + 4(x - 1)$

1 is subtracted from the total minutes because the first minute has a fixed rate.

For a 10 minutes call

$x = 10$

$y = 7 + 4(x - 1)$

$y = 7 + 4(10 - 1)$

$y = 7 + 4*9$

$y = 7 + 36$

$y = 43$

Hence, the charges for a 10 minutes call is: Rs.43