1 and 18
1 × 18 = 8
1+ 18 = 19
New pump:
5 hours = 1 pool
1 hour = 1/5 pool
Old pump:
15h = 1 pool
1h = 1/15 pool
If both work together
1h = 1/5 + 1/15 = 4/15 pool
4/15 pool = 1 hour
1/15 pool = 1/4 hour
15/15 pool = 1/4 x 15
1 pool = 3.75 hours or 3 hours 45 mins
The conclusion that is valid based on the result of the test would be : A. Her students on average, do not take 30 minutes on the quiz, contrary to what the textbook company stated
we can see in the statement that the average student only need about 25 minutes to take the quiz
hope this helps