(Use Solving Systems by Graphing to find a solution for this question) One cellphone provider DU charges AED10 per month plus an activation fee of AED20. A second cellphone provider ETISALAT charges AED11 per month plus an activation fee of AED15. For what number of months is the cost of either cellphone provider the same?

5 months

Step-by-step explanation:

One cellphone provider charges AED10 per month plus an activation fee of AED20.

If I used the services of this cellphone provider for x months, total charges for the services,

y = 10x + 20 (1)

Similarly, charges for the second cellphone provider for x months of uses will be,

y = 11x + 15 (2)

Input-output table for equation (1)

x      1           2            3            4            5

y     30        40         50          60          70

Input output table for equation (2)

x      1           2            3            4            5

y     26        37          48          59         70

From these tables, we find (5, 70) is a common point for both.

It reveals that after the uses of 5 months charges for both the cellphone providers will be same (y = $70)

"if it is my birthday, then it is snowing"

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!