Question

For her cellphone plan, Heather pays $30 per month plus $0.05 per tax. She wants to pay her bill under $60 a month. Which inequality represents the number of texts ,t, Heather can send each month while staying within her budget

Answer 1

Hi there! So the $30 is the fixed cost, and it cost $0.05 per text. Heather wants to keep her bill under $60. Keep in mind that the key word here is UNDER, which means the sign will be less than, not less than or equal to. For this situation, an inequality that represents the problem is this:

30 + 0.05t < 60

How to solve it:

Okay. Let's solve this inequality. First off, let's subtract 30 from both sides. 30 - 30 cancels out. 60 - 30 is 30. That makes the inequality 0.05t < 30. Now, divide each side by 0.05 to isolate the t. 0.05t/0.05 cancels out. 30/0.05 is 600. There. t < 600. Heather can send less than 600 texts and still stay within her budget.