A cell phone provider is offering an unlimited data plan for $70 per month or a 5 GB plan for $55 pe

A cell phone provider is offering an unlimited data plan for $70 per month or a 5 GB plan for $55 per month. However, if you go over your 5 GB of data in a month, you have to pay an extra $10 for each GB. How many GB would be used to make both plans cost the same?

Let g be the number of GB.

The limited plan has a cost as follows:
C = 10(g - 5) + 55
C = 10g - 50 + 55
C = 10g + 5

We want to set the limited plan equal to the unlimited plan and solve for g:
10g + 5 = 70

Solve for g in the equation 10g + 5 = 70

Step 1: Group constants:
We need to group our constants 5 and 70. To do that, we subtract 5 from both sides
10g + 5 - 5 = 70 - 5

Step 2: Cancel 5 on the left side:
10g = 65

Step 3: Divide each side of the equation by 10
10g/10 = 65/10
g = 6.5

Check our work for g = 6.5:
10(6.5) + 5
65 + 5
70