The partial circles in each corner mean that all 3 angles are identical, which means this is an equatorial triangle. In an equatorial triangle all three sides are the same.
We can set two of the equations to equal each other and solve for x:
3x -5 = 2x +20
Add 5 to each side:
3x = 2x +25
Subtract 2x from each side:
x = 25
Change in level is given by :
C = increase in level - decrease in level.
Now,
Decrease in level in March is 2 1/4 = 9/4 inches.
Increase in level in April is 1 5/8 = 13/8 inches.
Putting value of these in above equation, we get :
C = 13/8 - 9/4
C = 13/8 - 18/8
C = -5/8 inches
Therefore, the overall level after April will decrease by 5/8 inches.
Hence, option 4. is correct.
N/4 less than or equal to 5
A
- Harvard university professor
