Answer:
Samantha's grade was 1.29 standard deviations above the class mean, that is, she scored better than 0.9015 = 90.15% of the class.
Step-by-step explanation:
Z-score:
In a set with mean 
and standard deviation 
, the z-score 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 p-value, we get the probability that the value of the measure is greater than X.
In this question:
She scored better a proportion of the class given by the p-value of z = 1.29
z = 1.29 has a p-value of 0.9015.
Samantha's grade was 1.29 standard deviations above the class mean, that is, she scored better than 0.9015 = 90.15% of the class.
Answer:
4 cookies
Step-by-step explanation:
Let the number of cookies he sold be c and that of brownies be b.
Assuming that brownies and cookies are the only type of baked goods sold,
b +c= 10 -----(1)
Amount of money received= $20
b(cost of brownie) +c(cost of cookie)= $20
2.50b +1.25c= 20 -----(2)
From (1): b= 10 -c -----(3)
Substitute (3) into (2):
2.50(10 -c) +1.25c= 20
Expand:
2.50(10) +2.50(-c) +1.25c= 20
25 -2.50c +1.25c= 20
-1.25c +25= 20
Being constants to 1 side:
-1.25c= 20 -25
-1.25c= -5
c= -5 ÷(-1.25)
c= 4
Thus, Joe sold 4 cookies.
Answer:
.
Step-by-step explanation:
Given:
We need to find 
.
Solution:
Now we can see that given figure is a rectangle with diagonals drawn in it.
So by properties of rectangle which states that;
"All angles of a rectangle are 90°."
So we can say that;
But
Substituting the values we get;
Subtracting both side by by 31 we get;
Hence .
Answer:
x wouls be 0
Step-by-step explanation:
