If the mean score is 55% and the s.d. is 15%, then a test score of at least
55% + 1.5 × 15% = 77.5%
falls in the A range.
The next cutoff score is 0.5 s.d. from the mean, which is
55% + 0.5 × 15% = 62.5%
so any test score between 62.5% and 77.5% is in the B range.
The next cutoff is
55% - 0.5 × 15% = 47.5%
so a score between 47.5% and 62.5% gets a C.
The lower limit of the next range is
55% - 1.5 × 15% = 32.5%
so 32.5% - 47.5% gets a D.
Anything lower than 32.5% is an F.
Answer: b/65=7/13
65/13=5
35/7=5
Step-by-step explanation:
Answer:
2.5 or 2 1/2
Step-by-step explanation:
4 x 5= 20/8 = 2.5
:)))))
First you simplify both sides
Multiply -1 by x and 7
-x-7-16=x-3
Subtract -16 from -7
-x+9=x-3
Add 3. To both sides
-x+12=x
Add x to both sides
12=2x
Divide both sides by 2
6=x