Answer: A, D
Step-by-step explanation:
68 is the initial amount.
A is correct because 0.2(68) represents 20% of 68. Since you're looking for 80% of 68, you subtract 0.2(68) from 68.
D is correct because it directly takes 80% of 68, which is what the question is asking for.
Answer: it will take them 28 minutes to fill the tank.
Step-by-step explanation:
The first pipe alone can fill the tank in 84 minutes. This means that the rate at which the first pipe fills the tank per minute is 1/84
The second pipe can fill the tank in 42 minutes by itself. This means that the rate at which the second pipe fills the tank per minute is 1/42
If they work together, they would work simultaneously and their individual rates are additive. This means that their combined rate of filling the tank would be
1/84 + 1/42
Assuming it takes t hours for both pipes to fill the tank working together, the working rate per minute would be 1/t. Therefore,
1/84 + 1/42 = 1/t
3/84 = 1/t
t = 84/3
t = 28 minutes
(3x - 1) + 5
Hope this helps!
Answer:
C
Step-by-step explanation:
Using the tangent ratio in the right triangle
tanC = 
= 
= 
, then
C = 
( )
