Answer:
Step-by-step explanation:
a = 5b-10
a+b = 26
(5b-10)+b = 26
b = 6
a= 5b + 10 = 40
Answer:
The percentage of students who scored below 620 is 93.32%.
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 question, we have that:

Percentage of students who scored below 620:
This is the pvalue of Z when X = 620. So



has a pvalue of 0.9332
The percentage of students who scored below 620 is 93.32%.
1. No answer ( may be due to incorrect question)
2. x = -3
y = 4
3. x= 4
y = 2
4.x = -63/40
y= -19/20
Step 1
Multiply equation 1 by the coefficient of x in equation 2
Multiply equation 2 by the coefficient of x I'm equation 1
(after completing this step you will derive equation 3 and 4 )
Step 2
Subtract equation 4 from equation 3
Step 3
Divide both sides of the equation by the coefficient of y
Step 4
substitute your value for y in equation 1 or 2
(after this you will derive the values of x)
Note : This method is for the Elimination of x
I hope it helps
Answer: I'd go with C
Step-by-step explanation:
Answer:
15 is 40% of 37.5
Step-by-step explanation: