180/2=90 degree
180/3=60 degree
180/4=45 degree
Answer:
Year 7 = 75 students
Year 9 = 25 students
Step-by-step explanation:
Year 7 has 3/8 of the total since the circle is divided into 8 sections and has 3 of the 8 sections
3/8 * 200 students = 75
Year 9 has 1/8 of the total since the circle is divided into 8 sections and has 1 of the 8 sections
1/8 * 200 =25
Answer:
400cm^2
Step-by-step explanation
equation: a+b/2 x h
19+25/2 x 20
44/2 x 20
22 x 20
440 (don't forget unit) and to square because we are finding the area
Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
Answer:
w = -1/8
Step-by-step explanation:
-1/8 is like taking 1/8 from 7/8 making it 6/8 which = 3/4
