Answer:
The proportion of students whose height are lower than Darnell's height is 71.57%
Step-by-step explanation:
The complete question is:
A set of middle school student heights are normally distributed with a mean of 150 centimeters and a standard deviation of 20 centimeters. Darnel is a middle school student with a height of 161.4cm.
What proportion of proportion of students height are lower than Darnell's height.
Answer:
We first calculate the z-score corresponding to Darnell's height using:

We substitute x=161.4 ,
, and
to get:

From the normal distribution table, we read 0.5 under 7.
The corresponding area is 0.7157
Therefore the proportion of students whose height are lower than Darnell's height is 71.57%
Answer:
1 2/9 minutes faster
Step-by-step explanation:
Take the larger number and subtract the smaller number
8 5/9 minutes - 7 1/3 minutes
Get a common denominator
8 5/9 - 7 1/3 *3/3
8 5/9 - 7 3/9
1 2/9 minutes faster
Answer:
17.7
Step-by-step explanation:
angle B = 180 - 81 - 65 = 34 degrees
as the sum of all angles in any triangle is always 180 degrees.
a/sin(A) = b/sin(B) = c/sin(C)
the sides are always on the opposite side of the angle.
so,
10/sin(34) = AB/sin(81)
AB = 10×sin(81) / sin(34) = 17.7