A cell phone plan costs ​$29.80 per month for 800 minutes of talk time. It costs an additional ​$0.07 per minute for each minute over 800 minutes. To get​ e-mail access, it costs 20​% of the price for 800 minutes of talk time. Your​ bill, which includes​ e-mail, is the same each month for 8 months. The total cost for all 8 months is ​$320.80. Write and solve an equation to find the number of minutes of talk time you use each month.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.

answer is 12345678900987654321234567890987654321

step-by-step explanation:

the value of x is 28.2