Answer:
20.33%
Step-by-step explanation:
We have that the mean (m) is equal to 87.5, the standard deviation (sd) 6.25 and the sample size (n) = 12
They ask us for P (x <86)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / (sd / (n ^ 1/2))
We have all these values, replacing we have:
z = (86 - 87.5) / (6.25 / (12 ^ 1/2))
z = -0.83
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <-0.83) = 0.2033
The probability is 20.33%
Answer: 
Step-by-step explanation:
<h3>
The complete exercise is: " A theatre has the capacity to seat people across two levels, the Circle, and the stalls. The ratio of the number of seats in the circle to a number of seats in the stalls is 2:5. Last Friday, the audience occupied all the 528 seats in the circle and
of the seats in the stalls. What is the percentage of occupancy of the theatre last Friday?"</h3>
Let be "s" the total number of seats in the Stalls.
The problem says that the ratio of the number of seats in the Circle to the number of seats in the Stalls is
.
Since the number of seats that were occupied last Friday was 528 seats, we can set up the following proportion:

Solving for "s", we get:

So the sum of the number of seats in the Circle and the number of seats in the Stalls, is:
We know that
of the seats in the Stalls were occupied. Then, the number of seat in the Stalls that were occupied is:

Therefore, the total number of seats that were occupied las Friday is:
Knowing this, we can set up the following proportion, where "p" is the the percentage of occupancy of the theatre last Friday:

Solving for "p", we get:

OK, so this is assuming we are considering that the first three kids to solve ARE NOT in the first day.
So we have 3 kids and it doubles
Day 1 : 6
Day 2 : 12
Day 3 : 24
Day 4 : 48
Day 5 : 96
Day 6 : 192
Day 7: 384
So it should take 7 days or a week to solve all the problems.
The equation:
(3 * 2)^x = 384
120 minutes
Step by step:
divide 20 by 2.5 to find how many minutes it takes to drive 1 mile, then multiply that by 15 miles
Answer:
11.75 feet
Step-by-step explanation:
17 times 12 = 204 inches
204 - 63 = 141 inches
141/12 = 11.75 feet