I need more information than that, to answer this question. :/
(20 + 22 + 17) - 7 - 12 - (9 - x) = 37;
59 - 19 - 9 + x = 37;
31 + x = 37;
x = C) 6
Answer:
No, she doesn't have enough varnish for all the floors.
Step-by-step explanation:
Area of the floor, A= 10x6-5x2=50 
Since 5 m^2 required 1 liter of varnish.
So, the amount of varnish required for 1
= 1/5= 0.2 liters.
The amount of varnish required for 50
= 0.2X50=10 liters.
Now, as 1 tin has 2.5 liters of varnish.
So, the total amount of varnish available = 3x2.5=7.5 liters, which is less than the total requirement.
Hence, she doesn't have enough varnish for all the floors.
There are 8 girls in the class