There is a probability of 77% that the mean of this sample is between 19.25 hours and 21.0 hours
Z score is used to determine by how many standard deviations the raw score is above or below the mean. The z score is given by:
Given that μ = 20, σ = 7, n = 125.
For x = 19.25:
From the normal distribution table, P(-1.20 < z < 0.62) = P(z < 0.62) - P(z < -1.2) = 0.8849 - 0.1151 = 0.7698 = 77%
There is a probability of 77% that the mean of this sample is between 19.25 hours and 21.0 hours
Find out more on z score at: brainly.com/question/25638875
1. Original Equation
2. Subtract 6u from both sides
3. Combining 16u-6u you get 10u
4. Subtract 4 from both sides
5. Combining -21-4=4
6. Dividing by 10
7. The total of -25/10=-2.5
Your method is completely correct. The first term will be 6 and each subsequent term can be obtained by adding 6 to the previous one, meaning the common difference is 6. The number of terms is given by the highest number that is divisible by 6 and dividing it by 6; that is 996/6 = 166
Then we simply apply the formula for arithmetic sequence sum:
S = n/2 [2a₁ + (n - 1)d]
S = 166/2 [ 2(6) + (166 - 1)6]
S = 83,166
Answer :
x = 53.85
Step by step explanation:
If 78% of x (some numbers) is equal to 42, then we must set this as an equation to find it.
1) Rewriting 78% as a fraction and considering that when we say 78% of some number (x) we mean a product.
78% = 78/100 ➡️ 78/100x = 42
2) Then we can go on :
100 * 78/100x = 42 * 100
78x = 4200
78x/78 = 4200/78 ➡️ x = 53.85
3) Alternatively, simply dividing 42 by 0.78 (78%) would come to the same result :
42/0.78 = 53.85
Answer:
x equals five thirteenths
Step-by-step explanation:
To solve this, we will follow the steps below;
× x + 
= 4 × x
+ = 4x
= 4x
Multiply both-side of the equation by 4
× 4= 4x × 4
On the left-hand side of the equation 4 will cancel-out 4, thus the equation becomes;
3x + 5 = 16x
subtract 3x from both-side of the equation
16x - 3x = 5
13x = 5
Divide both-side of the equation by 13
= 
(On the left-hand side of the equation 13 at the numerator will cancel-out 13 at the denominator while on the right-hand side of the equation 5 will be divided by 13)
x =
x equals five thirteenths
