Answer:
19 coins
Step-by-step explanation:
We know that mean is the sum of all the elements divided by the number of elements there are: m = t/n, where m is the mean, t is the total sum, and n is the number of elements.
Here, we are given the mean number of coins for all 27 + 18 = 45 children is 16, so m = 16 and n = 45. Then:
m = t/n
16 = t/45
t = 720
This t means that the total number of coins that all the boys and girls have is 720 coins.
Now, we also know the mean number of coins for the boys only, which is 14. Since there are 27 boys, then:
m = t/n
14 = t/27
t = 378
This t means the total number of coins all the boys have.
Subtracting 378 from 720, we get 342, which is the total number of coins the girls have. We also know there are 18 girls, so:
m = t/n
m = 342 / 18 = 19
Thus, the mean is 19 coins.
Answer:
2.28% probability that a person selected at random will have an IQ of 110 or higher
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that a person selected at random will have an IQ of 110 or higher?
This is 1 subtracted by the pvalue of Z when X = 110. So



has a pvalue of 0.0228
2.28% probability that a person selected at random will have an IQ of 110 or higher
Answer:
3 cups of milk
Step-by-step explanation:
4/4 is 1 cup.
Answer:
It is open if it is greater or less than >
It is closed if it is greater than or equal to or less than or equal to > (but with the line underneath it)
Step-by-step explanation:
Answer:
(7.8, ∞)
Step-by-step explanation:
Given the inequality :
x > 7.8 ; the inequality can be explicitly interpreted as x greater than 8 ; this means that the inequality holds for all values of x above 7.8
The interval for which the inequality holds true is :
x > 7. 8 - - - > (7.8, ∞)