Step-by-step explanation:
Let the number of books of Physics be x . Then , No. of chemistry books =3.5x
Now , according to question :
x+3.5x=90
Or , 4.5x=90
Or , x=90/4.5
Or , x=20
Now ,
3.5x= 3.5×20
= 70
Therefore , there were 70 chemistry books and 20 physics books in that question bank.
Answer: D. A single number calculated from the sample that estimates a target population parameter is called a point estimator.
An interval estimator is a range of numbers that contain the target parameter with a high degree of confidence.
Step-by-step explanation:
When we evaluate an range of values for an unknown population parameter, then it is known as interval estimation .
A single number evaluated from the SAMPLE that estimates an unknown population parameter is known as a point estimator.
The general difference between point and interval estimator is the point estimator is a single value of target parameter while interval estimator is a range of numbers to estimate the values about the unknown population.
Answer:
C. 10–15, 15–20, 20–25, 25–30, 30–35
Step-by-step explanation:
Answer:
x=3, y=10
Step-by-step explanation:
in triangle KLN all the angles are equal making it an equilateral trianlge. GIven one side being 6, we know all the sides are 6 including the side with the expression y-4.
this means
y-4=6
y=10
Using the converse of the base angles theorem(meaning we know the base angles are congruent so the two sides are conguent), we know that
6=x+3
x=3
Answer:
175 square feet
Step-by-step explanation:
the area of the whole thing is 400 ft. (20 x 20=400)
i got the 20 from the perimeter b/c 20+20+20+20=80
then subtract the area of the pool from 400 to get 175.