H=-16t^2+56t+1, the airplane is shot up from a platform 1 foot above the ground, so 1= - 16t^2+56t+1, we solve this equation
(- 16t+56)t=0, (- 16t+56)=0 or t=o, - 16t+56=0, implies t =3.5s
so the answer is C)3.5 seconds
Answer:
x=4
y=7
Step-by-step explanation:
12=3x
x=4
6=y-1
y=6+1
y=7
Answer:
89.88 gallons of milk
Step-by-step explanation:
97.88-8=89.88
Answer:
the students that brought a lunch box is 28
Step-by-step explanation:
The computation of the students that brought a lunch box is shown below:
= Entire school students × students that carry a lunch box ÷ entering students
= 84 students × 8 ÷ 24 students
= 28 students
Hence, the students that brought a lunch box is 28
Answer:

And we can assume a normal distribution and then we can solve the problem with the z score formula given by:

And replacing we got:


We can find the probability of interest using the normal standard table and with the following difference:

Step-by-step explanation:
Let X the random variable who represent the expense and we assume the following parameters:

And for this case we want to find the percent of his expense between 38.6 and 57.8 so we want this probability:

And we can assume a normal distribution and then we can solve the problem with the z score formula given by:

And replacing we got:


We can find the probability of interest using the normal standard table and with the following difference:
