Answer:
-2.5
Step-by-step explanation:
Here in this question, we are interested in calculating the z-score for a student that had a particular mark at the test
To calculate the z-score, we need to use a mathematical formula
Mathematically;
z-score = (x - mean)/SD
From the question;
x = 76
mean = 86
standard deviation SD = 4
Plugging these values in the equation, we have;
z-score = (76-86)/4 = -10/4 = -2.5
Answer:
y=1
You can put equations in a graphing calculator if you aren't sure.
Answer:
Y = 32.7°
Step-by-step explanation:
We will apply the Cosine law in the given triangle XYZ,
x = 90 ft
y = 55 ft
z = 50 ft
We have to find the measure of angle Y.
y² = x² + z² - 2xzCosY
(55)² = (90)² + (50)² - 2(90)(50)cosY
3025 = 8100 + 2500 - 9000.cosY
9000.cosY = 10600 - 3025
cosY =
= 0.84167
Y =
Y = 32.68 ≈ 32.7°
Therefore, measure of angle Y = 32.7°
Answer:
6.8% decrease
Step-by-step explanation:
a drop of 8% means that only 92% of 125 boys remained on honor roll from last year; .92 x 125 = 115
a drop of 5% means that only 95% of 80 girls remained on honor roll from last year; .95 x 80 = 76
total number of students on honor roll last year = 125 + 80 = 205
total number of students on honor roll this year = 115 + 76 = 191
percent of change = (191 - 205) ÷ 205 = -14/205 = -.068
-.068, which represents a 6.8% decrease