Set of equations that can be used to calculate rate for each plumber:
2A+8B+8C = 1,400 --- (1)
4A+7B+10C = 1,660 --- (2)
3A+9B+9C = 1,660 --- (3)
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2*(1) - (2)
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4A+16B+16C = 2,800
4A+7B+10C = 1,660 -
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9B+6C = 1,140 --- (4)
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3(2) -4(3)
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12A+21B+30C = 4,980
12A+36B+36C = 6,600 -
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-15B-6C = -1,620 --- (5)
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(4) + (5)
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9B+6C = 1140
-15B-6C = -1620 +
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-6B = -480 => 6B = 480 => B = 480/6 = 80
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Using (4), 9(80)+6C = 1140
720+6C = 1140 => 6C = 1140-720 = 420 => C = 420/6 = 70
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Using (1), 2A+8(80)+8(70) = 1400
2A+640+560 =1400 => 2A = 1400-640-560 = 200 => A = 200/2 = 100
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The rates are:
A = $100
B = $80
C = $70
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On Thursday, number of calls: A = 4 hrs, B = 6 hrs, C = 3 hrs
Money earned = 4*100+6*80+3*70 = $1,090
Answer:
ab
Step-by-step explanation:
When all of the variables are the same in a problem, think of them as the same term. They can be added and subtracted just as you would add and subtract normal numbers.
For example if I have 5 bananas on a table and take away 3 bananas. I only have two bananas left (2b). It's the same when there are variables!
Subtract 9 from 3:
-6ab+7ab
Add -6 to 7:
ab
Your final answer is ab!
Answer:
Since it is the case of independent the answer will be 6/22
Answer:
Step-by-step explanation:
Air pressure is measured in pascals. For a professional American football game, the ball should be inflated to about 90,000 pascals. Scientists studied the effects of air temperature on the pressure inside American footballs by taking these steps:
1. Prepare 100 footballs.
2. Measure each football's air pressure.
3. Divide footballs into 10 groups.
4. Place the groups in different lockers cooled to different air temperatures.
5. After 12 hours, remove the footballs from lockers.
6. Measure each football’s pressure again.
7. Compare the new pressures to the starting pressures.
What two terms best describe the variable "air pressure inside the football" in this experiment?
independent, qualitative
independent, quantitative
dependent, qualitative
dependent, quantitative
Answer:
1620 people ride each week.
Step-by-step explanation:
30 x 9 = 270
270 x 6 = 1620
