For A B and C, you just plug in the given number
A

B

C

And for D, you set the equation to 26 and solve for n

I had to use x instead of n, but for D n=7. :)
Step-by-step explanation:
the number of pupils are in the lower school
= (1- 1/5 - ¼) × 600
= (20/20 - 4/20 - 5/20)×600
= (11/20) ×600
= 330 pupils
Answer:
D
Step-by-step explanation:
<u>Answer</u>
C. 39.71
<u>Explanation</u>
33 = p - 6.71
The first step is to make the like terms to be on the same side.
Add 6.71 on both sides of the eqution
33 + 6.71 = p - 6.71 + 6.71
39.71 = p
∴ p = 39.71
I think you would use the Pythagorean Theorem to solve this, as a square cut across diagonally creates two isocele triangles. Since the longest side is 20 m, this value would be imputed into c^2.
a^2 + b^2 = c^2
a^2 + a^2 = 20^2
2a^2 = 400
2a^2/2 = 400/2
a^2 = 200
a = 14.14
Thus, each sides of the playground are 14.14 meters long.