Answer:
(96.91, 101.09)
Step-by-step explanation:
To calculate the interval, you require the Z value at 95% confidence interval. The Z value is 1.96. The formula to calculate the confidence interval:
Where X is the mean and s is the standard deviation and x the sample size:
The interval is (96.91, 101.09)
Mom drove for 11 hours.
Dad drove for 3 hours.
<u>Step-by-step explanation</u>:
- Total distance = 895 miles
- Mom drove a speed of 65 mph
- Dad drove a speed of 60 mph
Let 'x' be the number of hours drove by mom.
Let 'y' be the number of hours drove by dad.
x + y = 14 ---------------(1)
65x + 60y = 895 ---------(2)
Multiply eq(1) by 60 and subtract eq(2) from (1),
60x + 60y = 840
-(<u>65x + 60y = 895</u>)
<u> -5x = -55 </u>
x = 55/5
x = 11
∴ Mom drove for 11 hours.
Substitute x=11 in eq(1)
11+y = 14
y = 3
∴ Dad drove for 3 hours.
Answer:
a and d
Step-by-step explanation:
i took the test
Answer:
45.29 miles per hour
Step-by-step explanation:
Speed is the distance over time. To find the average rate of speed for a trip, we simply need to take the total distance divided by the total time.
Avg. Speed = (188 miles + 197 miles) / (4 hours + 4.5 hours)
Avg. Speed = 45.29 miles per hour
Hence the average rate of speed for the trip was 45.29 miles per hour.
Cheers.
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Edit: Thanks to Chegsnut36 for calculation correction
