Add them all up and then divide by 5. The answer is 1.493
Let x be the number of 20 ton cars
Then,
380<{15(22-x)+20x}<400
380<{330-15x+20x}<400
380<{330+5x}<400
Subtract 330 on both sides
50<5x<70
Divide both sides by 5;
10<x<14
Therefore, the range of 20 tonne cars is between 10 and 14 cars.
K = 1.2
Short answer.It's going to seem odd, but one of the ways you could solve this is by multiplying the first equation by 4. I'll tell you why in a moment.
4(0.3x - 0.7y = 1) Now remove the brackets.
1.2x - 2.8y = 4 If you want there to be no solution, the way to do it is the make k = 1.2 The second equation becomes.
1.2x - 2.8y = 3
I'm going to give you the graph of this so you will see why there is no solution. Do you see why?
The lines are parallel!! they never meet.
Answer:
She has a class of 17 kids. At $24 each, she can spend 17*$24 = $408. Since she spent $125.36, she has $408 - $125.36 = $282.64 left to spend.
Step-by-step explanation: