Answer:c
Step-by-step explanation:
If 22% are sixth graders, then the rest must not sixths graders.
100% of the school - 22% sixth grades = 78% are not sixths graders
This can be solved by using the normal approximation to the binomial distribution.
mean = np = 10.000 * 0.5 = 5,000
The standard deviation is given by:


The probability of obtaining more than 5100 tails is 0.0228 and the probability of obtaining fewer than 5100 tails is 0.9772.
The odds of obtaining more than 5100 tails is therefore:
0.0228:0.9772 = 1:42.86.
Answer:
C
Step-by-step explanation:
Anything less than 5 rounds down while 5 and anything more rounds up. Therefore...
15.3 rounds to 15
7.9 rounds to 8
7.4 rounds to 7
So, his answer is reasonable.
A) Perimeter of Trapezium = 8+5+6+15.5
= 34.5in
Area= 1/2*(a+b)*h
=1/2*(8+15.5)*4
=47in^2
B)Perimeter= 12+6+8.5
=26.5mm
Area=1/2*b*h
=1/2*12*4
=24mm^2