Answer:
10
Step-by-step explanation:

There are 10 packages of paper in each pile.
------------------------------------------------------------------
Check:
There are 7 piles.
Thus, there are
total packages of paper.
Either
if he pays her back: 42.80-12 --------- this would equal 30.80
or if she pays him back 42.80+ 12------- this would equal 54.80
Answer:
see the attachment
Step-by-step explanation:
The ceiling of numbers between -1 and 0 (not including -1) will be 0. Adding 3 to that moves the segment up to y = 3. Hence, the last graph is the appropriate one.
Any integer is its own ceiling, and it is also the ceiling of numbers between that and the next lower integer. Hence each segment on the graph will have an open circle at the left end and a closed circle at the right end.
Answer:
.7147
Step-by-step explanation:
Let P be the probability of 55 families having mean more than 17
P { (17-17.2)/ (2.5/√55) }
P(- 0.5933 )
= - .2765 [ From the z table ]
P be the probability of 55 families having mean less than 18
P { (18 -17.2)/ (2.5/√55) }
P( 2.3732 )
= .9912 [ From the z table ]
Probability of mean between 17 and 18
= .9912 - .2765
= .7147