Answer:
If the pool is 2/3 filled and then the inlet pipe and drain pipe are opened, it will take 140 hours to fill the pool
Step-by-step explanation:
An inlet pipe can fill the pool in hours = 20
Inlet pipe 1 hour work = 
A drain pipe can empty the pool in 21 hours
Drain pipe 1 hour work =
Inlet pipe and drain pipe 1 hour together work = 
Now we are given that the pool is 2/3 filled
So, remaining portion to be filled =
So, Inlet pipe and drain pipe fill 
in hours = 1
So, they can fill 1/3 in hours = 
Hence If the pool is 2/3 filled and then the inlet pipe and drain pipe are opened, it will take 140 hours to fill the pool
Answer:
10
Step-by-step explanation:
Answer:
No y
Step-by-step explanation:
Since
x=-1
is a vertical line, there is no y-intercept and the slope is undefined.
Answer:
If the directions say write an equation: 2n + 5 =25
If the directions say also to solve the equation and find the number: 10
Step-by-step explanation:
"The sum" means we're using adding. So what things are we adding together? The question says "twice a number" and 5. Well we've got the 5. And "twice" means two times. And "a number" means we don't know the number yet, so we choose a variable, like n.
"Twice a number" can be written 2n.
So far we have:
2n + 5 is 25
We use = for the "is" in this sentence.
2n + 5 = 25
Now we can solve it.
Subtract 5 from both sides.
2n = 20
Divide by 2 on both sides.
2n/2 = 20/2
n = 10
The number is 10.
