Answer:
a4 = 128
a5 = -512
Step-by-step explanation:
a1= -2
q= (-1)^(n+1) × 4
a4 = a1q³ = (-2) (-4)³ = -2 × -64 = +128
a5 = a1q⁴ = (-2) (-4)⁴ = -2 × 256 = -512
The number of people in the sample survey is 75.
Survey sampling, as used in statistics, is the process of choosing a sample of constituents from a target population to perform a survey. The word "survey" can be used to describe a wide range of observational methods or procedures. Most frequently, a questionnaire meant to assess people's traits and/or opinions is employed in survey sampling. The topic of survey data collecting involves various methods of contacting sample participants after they have been chosen. Sampling is done to cut down on the expense and/or labor required to survey the complete target population. A census is a survey that includes all members of the target population. A sample is a subset or segment of a population from which data will be drawn.
The sample survey has
5 people in 1-4 miles per week
10 people in 5-8 miles per week
15 people in 9-12 miles per week
20 people in 13-15 miles per week
25 people in 16-19 miles per week
The number of people in the sample survey is
5 + 10 + 15 + 20 + 25
=5(1 + 2 + 3 + 4 + 5)
=5(15)
=75
Hence, the number of people in the sample survey is 75.
Learn more about sampling survey here-
brainly.com/question/24564273
#SPJ10
Answer: Time it took her to get to the school is 0.6 hours
The distance of the school from their home is 27 miles
Step-by-step explanation:
Mrs Dang drove her daughter to school at the average speed of 45 miles per hour.
Let x miles = distance from the school to their home.
Distance = speed × time
Time = distance / speed
Time used in going to school will be
x/45
She returned home by the same route. This means that distance back home is also x miles.
She returned at an average speed of 30 miles per hour.
Time used in returning home from school will be x/30
x/45
If the trip took one half hour, then the time spent in going to school and the time spent in returning is 1 1/2 hours = 1.5 hours. Therefore
x/30 + x/45 = 1.5
(15x + 10x) /450 = 1.5
15x + 10x = 450 × 1.5 = 675
25x = 675
x = 675/25 = 27
Time it took her to get to the school will be x/45
= 27/45 = 0.6 hours
Answer:wdym?
Step-by-step explanation:
