Question

Mr. Keskin and his wife have a cell phone plan that charges them $5 for 200 text messages per month for each of their phones. The Keskins are charged an additional $0.12 for each text message over their 200-text-message limit. Their carrier has offered them unlimited text messages for both lines for $30. What is the maximum number of text messages that they can send in a month to keep their current plan as the better deal? What is the minimum? Explain.

Answer 1

for m minutes,
current plan: 5.00 + .12(m-200)
proposed plan: 30.00

so, we want solve

5.00 + .12(m-200) < 30.00
m < 409

Answer 2

Please explain, i'm having trouble understanding.

Answer 3

do you understand the expressions for the current and proposed plans? Those are just symbols for the words that described the plans. Read the problem carefully, and wherever they give some information, write it down in numbers or symbols.

To solve for m, just do the regular steps for solving an equation:

5.00 + .12(m-200) < 30.00
5.00 + .12m - 24 < 30
.12m < 49
m < 408.3

Assuming charges are for whole messages, that means m < 409.

Answer 4

Ohh ok thank you! I understand now!