143 seats
because 2920 seats/20 sections=143 seats in each section
Answer:
x + y = 4 Equation 1
y = 2x -1 Equation 2
-2x + y = -1
x + y = 4
Subtract
You will get
- 3x = -5
Divide by -3
-3x / -3 = - 5 /-3
x = 5/3
Substitute x into equation 1
x + y = 4
x = 5/3
5/3 + y = 4
y = 4 - 5/3
y = 7/3
x = 5/3 y = 7/3
Hope this helps.
Selection B is appropriate.
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It takes 12 times as long to fill the whole tank as it does to fill 1/12 of the tank.
.. 12 * (1/3 hour) = (1/3)*12 hour
I) 80% x 5640 = Rs. 4512
ii) 4512 divide by 50 = Rs. 90.24