Answer:
Step-by-step explanation:
n = 400
Proportion p = 229/400= 0.5725
For 95% confidence interval we use Z value as 1.96
Std error = 0.025
margin of error = 1.96*0.025
Confidence interval 95% = 0.5725±Margin of error
= (0.524, 0.621)
b) When smiled x becomes 277
p = 0.6925
Std error = 0.023
Margin of error= 1.96*0.023
Confidence interval = (0.647, 0.738)
Smiling increases the chances of stopping since mean and conidence interval bounds are showing increasing trend.
Answer:20 ^v^ Please follow me
Step-by-step explanation:
200/40=5
5+15=20
Answer:
500 X 7 = 3500, 3500m = 3.5 km
She walked 3.5 km in 1 week.
Answer:
c=72
Step-by-step explanation:
8
=
9
8
⋅
8
=
8
⋅
9
Answer:
4
Step-by-step explanation:
one person is deemed to drive and that person is fixed on the driver's seat no mater which arrangement.
we have now 2 more seats one adjacent to the driver and one rear (two combined).
so the total ways in which all five can be arranged is as follows.
driver, adjacent to him(1) and three back.
driver adjacent to him (different person) and three back.
see the driver is always fixed so we can ignore him.
thus we when driver set fixed , on two remaining seats (adjacent to driver and the back )there can be 4 different combinations.
