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:
Yes, x = 33 is a solution
Step-by-step explanation:
To see if it is a solution, plug in 33 as x
3 = x/11
3 = 33/11
3 = 3
Since this is correct, x = 33 is a solution.
The answer is A. A^2+b^2=c^2
We know that the right triangle has one 90 degree angle and two acute (< 90 degree) angles. Since the sum of the angles of a triangle is always 180 degrees.
<u>To find x:</u>
(10x - 20) + (6x + 8) = 180
16x - 12 = 180
+12 +12
16x = 192
----- -----
16 16
x = 12
<u>Check:</u>
(10(12) - 20) + (6(12) + 8) = 180
(120 - 20) + (72 + 8) = 180
100 + 80 = 180
180 = 180
<u>Angle (10x - 20):</u>
(10(12) - 20)
(120 - 20)
100
<u>Angle (6x + 8):</u>
(6(12) + 8)
(72 + 8)
80
