Answer: -5
Step-by-step explanation:
Answer:
The speed of the first train is 45 mph and the speed of the second train is 75 mph
Step-by-step explanation:
Let x represent the speed of the first train in mph. Since the second train, is 30 mph faster then the first, therefore the speed of the second train is (x + 30).
The first train leaves at 1:00 pm, therefore at 6:00 pm, the time taken is 5 hours. Therefore the distance covered by the first train at 6:00 pm = x mph * 5 hours = 5x miles
The second train leaves at 3:00 pm, therefore at 6:00 pm, the time taken is 3 hours. Therefore the distance covered by the second train at 6:00 pm = (x + 30) mph * 3 hours = (3x + 90) miles
Since the second train overtakes the first at 6:00 pm, hence:
3x + 90 = 5x
2x = 90
x = 45
Therefore the speed of the first train is 45 mph and the speed of the second train is 75 mph (45 mph + 30 mph).
Answer: n = 600.25 ≈ 601 ( sample size)
the minimum sample size of the adults in United State who have sleep deprivation is 601
Step-by-step explanation:
Given that;
the confidence level = 95% = 0.05
the Margin of error E = 4% = 0.04
∴ level of significance ∝ = 1 - C.L
∝ = 1 - (95/100)
= 0.05
Z∝/2 = 0.05/2 = 0.025
Z-critical value at 95% confidence level is OR level of significance at 0.025 = 1.96 (z-table)
Now to calculate the sample size, we say
n = (Z(critical) / M.E )² P ( 1 - P)
now we substitute
n = (1.96 / 0.04)² × 0.5 ( 1 - 0.5)
n = 2401 × 0.5 × 0.5
n = 600.25 ≈ 601
Therefore the minimum sample size of the adults in United State who have sleep deprivation is 601
4:9
24:x
Set up a proportion
4/9=24/x
4x=216
x=54
a) 54 is your answer
hope this helps, and please give brainliest if it does!
