Cost of month plan = $40
Cost of minutes used = $0.45 after 700 minutes
Total cost = $48.10
Let x be the total minutes used
Total cost = 40 + 0.45(x - 700)
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Form the equation and solve x
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40 + 0.45(x - 700) = 48.10
40 + 0.45x - 315 = 48.10
0.45x - 275 = 48.10
0.45x = 48.10 + 275
0.45x = 323.10
x = 323.10 ÷ 0.45
x = 718
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Answer: John had used 718 mins this month
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Answer:
No solution
Step-by-step explanation:
2x - 8 + 3x > 5x - 4
2x + 3x - 8 > 5x - 4
5x - 8 > 5x - 4
-5x +8 > -5x +8
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0x > 4
This is no solution, as there is no 'x' value.
(0x just means there isn't anything left, I put that in order to show there wasn't anything.)
We're going to be using combination since this question is asking how many different combinations of 10 people can be selected from a set of 23.
We would only use permutation if the order of the people in the committee mattered, which it seems it doesn't.
Formula for combination:

Where
represents the number of objects/people in the set and
represents the number of objects/people being chosen from the set
There are 23 people in the set and 10 people being chosen from the set


Usually I would prefer solving such fractions by hand instead of a calculator, but factorials can result in large numbers and there is too much multiplication. Using a calculator, we get

Thus, there are 1,144,066 different 10 person committees that can be selected from a pool of 23 people. Let me know if you need any clarifications, thanks!
~ Padoru
The same would be the right one
Answer:
135
Step-by-step explanation:
Well 3 friends and 45 dollars each
45*3=135