Answer:
25 students take both subjects.
Step-by-step explanation:
Solve for 60% of 300 students:
60/100 = x/300
Cross multiply:
60 × 300 = 100 × x
18000 = 100x
Divide both sides by 100:
180 = x
Solve for 20% of 300 students:
20/100 = x/300
20 × 300 = 100 × x
6000 = 100x
60 = x
Solve for the percentage of students in chemistry:
x/100 = 35/300
x × 300 = 100 × 35
300x = 3500
x = 11.66666...7
x = about 11.7%
Find the difference in percentages:
100 - 60 - 20 - 11.7
8.3
8.3% take both subjects
Solve for 8.3% of students:
8.3/100 = x/300
8.3 × 300 = 100 × x
2490 = 100x
24.9
About 25 students
Check your work by adding all the students together (to get to 300):
25 + 60 + 180 + 35
300 students total
This is correct!
Answer:
512
Step-by-step explanation:
Answer:
The sample size must be approximately 211.
Step-by-step explanation:
We are given the following in the question:
Sample mean, = 654.1
Alpha, α = 0.02
Population standard deviation, σ = 311.7
Margin of error = 50
Formula:
Putting all the values, we get,
Thus, the sample size must be approximately 211.
Answer:
3.6ft per min
Step-by-step explanation:
Answer:
Volume= 216 cubic yards
Surface area: 276 square yards
Step-by-step explanation:
Find volume of rectangular prism:
V= lxwxh
V= 3x18x4
= 216 cubic yards
Find surface area:
SA= 2 x (front/back area) + 2 x (right/left area) and 2 x ( bottom/top area)
Front and Back Area:
A= l x w
A = 18 x 3
= 54 square yards
Right/ left Area:
4 x 3
= 12 square yards
Top/ Bottom Area:
18 x 4
= 72 square yards
54^2+12^2+72^2
= 108+24+144
=276 square yards