Answer: 110
Step-by-step explanation:
Answer:
x=17
Step-by-step explanation:
We have been given that the ages of students in a school are normally distributed with a mean of 15 years and a standard deviation of 2 years.
We are asked to find the percentage of students that are between 14 and 18 years old.
First of all, we will find z-score corresponding to 14 and 18 using z-score formula.




Similarly, we will find the z-score corresponding to 18.



Now we will find the probability of getting a z-score between
and
that is
.

Using normal distribution table, we will get:


Let us convert
into percentage.

Therefore, approximately
of the students are between 14 and 18 years old.
If you cut the rectangle (the wall) diagonally, you get two congruent triangles. The measurements of the sides of one the triangles is 8, 15 and x. There is a pythagorean triples 8, 15, 17 so x has to be 17. if you dont know the triple you can do a^2 + b^2 = c^2 8^2 + 15^2 = c^2 c = 17
the diagonal of wall should be 17