Let x be the number of red fish
3:5 = x:20
3/5 = x/20
(Cross method)
5x = 60
x =12
There are 12 red fish in the fish tank.
I got:
-2(2f-3g)
explanation:
used communicative property
<span>52 + 53 - 54 = 51
</span>None of them is the answer
The answer is 769.3 cm²
The volume of the cylinder is : V = π r² h
<span>The ratio between the radius of the base and the height of the cylinder is 2:3:
r/h = 2/3
h = 3/2r
V = 1617 cm
</span>π = 3.14
1617 = πr² * 3/2 r
1617 = πr³ * 3/2
1617 * 2/3 = πr³
1078 = πr³
r³ = 1078/π = 1078/3.14 = 343
r = ∛343 = 7 cm
h = 3/2r = 3/2 * 7 = 10.5 cm
The surface area of the cylinder is:
SA = 2πr² + 2πrh
= 2 * 3.14 * 7² + 2 * 3.14 * 7 * 10.5
= 307.72 + 461.58
= 769.3 cm²
