Answer:
Option A is correct
Step-by-step explanation:
Given: FH is the altitude to the hypotenuse EG
To find: length of FH
Solution:
According to Pythagoras theorem, square of hypotenuse is equal to sum of squares of other two sides.
In ,
So,
Put EH = 6 units and EF = 7 units
Option A is correct
Take square root on both sides
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