Answer:
a) 0.283 or 28.3%
b) 0.130 or 13%
c) 0.4 or 40%
d) 30.6 mm
Step-by-step explanation:
z-score of a single left atrial diameter value of healthy children can be calculated as:
z=
where
- X is the left atrial diameter value we are looking for its z-score
- M is the mean left atrial diameter of healthy children (26.7 mm)
- s is the standard deviation (4.7 mm)
Then
a) proportion of healthy children who have left atrial diameters less than 24 mm
=P(z<z*) where z* is the z-score of 24 mm
z*=
≈ −0.574
And P(z<−0.574)=0.283
b) proportion of healthy children who have left atrial diameters greater than 32 mm
= P(z>z*) = 1-P(z<z*) where z* is the z-score of 32 mm
z*=
≈ 1.128
1-P(z<1.128)=0.8703=0.130
c) proportion of healthy children have left atrial diameters between 25 and 30 mm
=P(z(25)<z<z(30)) where z(25), z(30) are the z-scores of 25 and 30 mm
z(30)=
≈ 0.702
z(25)=
≈ −0.362
P(z<0.702)=0.7587
P(z<−0.362)=0.3587
Then P(z(25)<z<z(30)) =0.7587 - 0.3587 =0.4
d) to find the value for which only about 20% have a larger left atrial diameter, we assume
P(z>z*)=0.2 or 20% where z* is the z-score of the value we are looking for.
Then P(z<z*)=0.8 and z*=0.84. That is
0.84=
solving this equation for X we get X=30.648
The answer is: [A]: " 2 × 3 × 5 × 7 " .
________________________________________________________
210 = 70 * 3 ;
70 * 3 = 35 * 2 * 3 ;
35* 2* 3 = 7 * 5 * 2 * 3 ; which corresponds to "Answer choice: [A]." .
________________________________________________________
(6x + 30)+(2x+6)= 180
8x +36= 180
8x= 144
X= 18
So 2x+6 = 42
And 6x+30 = 138
Answer:
714
Step-by-step explanation:
So lets go over what we know.
The bus only goes for 6 hours each day.
So lets just think of a full day as 6 hours.
Each day(6 hours), 4284 passangers ride the bus.
To find passangers per hour, we must divide the total passangers by the total hours.
This is 4284(total passangers) divided by 6(total hours):
4284/6
=
714
So each hour, there are 714 passangers.
Hope this helps!