Answer: 100
5
Step-by-step explanation:
a) The mean of a normal distribution is also the median. Half the population will have values above the mean. Half of 200 is 100, so ...
... 100 students will have grades above 70%.
b) 84% is 14% above the mean. Each 7% is 1 standard deviation, so 14% is 2 standard deviations above the mean. The empirical rule tells you 95% of the population is within 2 standard deviations of the mean, so about 5% of students (10 students) got grades higher than 84% or lower than 56%. The normal distribution is symmetrical, so we expect about 5 students in each range.
... about 5 students will have grades above 84%.
Answer: 5.5 seconds
Step-by-step explanation:
30=5/4 ×(-20) + 10t
30 =-25 +10t
10t=55
t=5.5seconds
The cord will first touch the corner of the building after 5.5secs
6+2(x+8)+3x+11+x
First you have to expand the brackets:
6+2x+16+3x+11+x
Now you group like terms (terms with the same or no variable):
2x+3x+x+11+16+6
And finally, combine like terms:
6x+33
Hope this helps :)
Answer:
Area = 14.5
Step-by-step explanation:
Let's label the given coordinates A, B, C;
Thus;
A = (2, 3)
B = (-1, 0)
C = (2, -4)
From the coordinate geometry formula, the formula for area of a triangle with 3 vertices is;
Area = [Ax(By - Cy) + Bx(Cy - Ay) + Cx(Ay - By)]/2
Area = [2(0 - (-4)) + (-1)(-4 - 3) + 2(3 - (-4))]/2
Area = 29/2
Area = 14.5
