Let’s make 2:3 is the same as 8:12. This means that there are 12 girls in the home room.
Equation
Let the number = x
(2/3)x + x = 20 Change the x to thirds.
(2/3)x + 3/3x = 20 3/3 = 1 Now combine the like terms.
(2 + 3)/3 = 20 2/3 + 3/3 = 5/3
(5/3) x = 20 Multiply both sides by 3/5
(5/3)*(3/5)x = 20*3/5 Complete the multiplication on the right
x = 4 * 3 Combine
x = 12 Answer
Answer: 17/32 or 9/16 if the first one is not an option
Step-by-step explanation:
Answer:
The Sample Size Need To be at least 114
Step-by-step explanation:
According to the Question,
- Given, A university dean of students wishes to estimate the average number of hours students spend doing homework per week. The standard deviation from a previous study is 6.2 hours.
The Maximum Error(E) is given as 1.5 hours and the standard deviation(σ) is 6.2 hours.
- Now, For 99% Confident the level of value α is 0.01.
α/2 = 0.01/2 ⇒ 0.005
- Thus, From The table, We get that the value of
is 2.58.
Hence, the sample size n can be found as
n = {
}²
n = {2.58 × 6.2}² / 1.5²
n = 113.72 .
So, The Sample Size Need To be at least 114.