Question

A long distance phone call costs $10.00 for the first ten minutes and $0.75 for each additional thirty seconds. If Andre has $16.65, he can talk for

(A) 13 minutes and 30 seconds
(B) 14 minutes
(C) 14 minutes and 30 seconds
(D) 15 minutes
(E) 17 minutes and 30 seconds

Answer 1

@phi @jim_thompson5910

Answer 2

were you able to set up the equation?

Answer 3

I have
\[$10 + $0.75x = $16.65\]

I am not sure if that's correct

Answer 4

good, where x is the number of 30 second intervals (after the 10 minutes are used up)

Answer 5

solve for x to get x = ??

Answer 6

It's like a decimal that can be rounded to 8.87

Answer 7

let's make x a whole number

so round that down to x = 8

Answer 8

we don't round up to x = 9 because then we'd go over budget

Answer 9

if x = 8, then he can talk an additional 8*30 = 240 seconds = 4 minutes

Answer 10

30 x 9 = 270 seconds

Answer 11

no, like I said, we can't bump up to 9 because we'd go over our budget

Answer 12

oh sorry

Answer 13

i meant to put 30 x 8

Answer 14

240 seconds / 60 seconds = 4 minutes

14 minutes

Answer 15

is that correct ?

Answer 16

yep, 14 minutes is the final answer

Answer 17

thank you!

Answer 18

no problem