Answer:
There are 1240 students at Washington middle school.
Step-by-step explanation:
Percentages and Portions
We can find portions of a whole by correctly managing the percentages of each part. We know 25% of all students at Washington middle school were on the honor roll. From that portion, 60% of the students are seventh graders. That means 40% of the 25% are eight graders, i.e. 40*25%=10% were from eight grade.
We have 10% of all students are 124, thus the number of students are 124/10%=1240
There are 1240 students at Washington middle school.
Let's test the answer. 25% of 1240 students are on the honor roll, which is 310 students. 40% of 310 students are from 8th grade, 40%*310 = 124 as stated in the problem
Answer:
Sample mean
Sample variance
Sample proportion
Step-by-step explanation:
Answer:
-8
Step-by-step explanation:
(-8.0)=-8
Answer:
The average speed over the time interval from 9 A.M. to noon was of 33.33 mph.
Step-by-step explanation:
The average speed is given by the following equation:
From 10A.M. to noon.
You traveled at 50mph during 2 hours. So how long you traveled?
You traveled 100 miles.
What was your average speed over the time interval from 9 A.M. to noon
From 9 A.M. to 10 A.M, you did not travel.
From 10 P.M. to noon, 100 miles.
So 100 miles during 3 hours.
The average speed over the time interval from 9 A.M. to noon was of 33.33 mph.
Answer:
x = ± 10
Step-by-step explanation:
Given
x² - 100 = 0 ( add 100 to both sides )
x² = 100 ( take the square root of both sides )
x = ± ← note plus or minus, hence
x = ± 10