Answer:
4.6 hours
Step-by-step explanation:
we first need to calculate the total distance he covered and total time taken whole for the journey.
Distance= speed X time
time = Distance/speed
let the total distance be X. he covers 2/5 if the journey first.
2/5 = 0.4
Time = 0.4x/45 hours
the remaining journey is 3/5x
he covers 1/3 X 3/5= 0.2x
time taken = 0.2/90 X hours
the remaining distance = 100× 1.2 = 120km
we add 0.4x + 0.2x to get the fraction he had covered
0.6x.
the remaining distance was X - 0.6x = 0.4 X
thus 120 km represents 0.4x of the journey
we calculate now the value of X
0.4x = 120
X = 300km
Total time taken = 0.4x/45 + 0.2/90 + 1.2 hours
replace X to get time
2.7 hours + 0.7 hours + 1.2 hours
= 4.6 hours
The right answer for the question that is being asked and shown above is that: "The southern California study with a margin of error of 4.9%." the study has the smallest margin of error for a 98% confidence interval is that The southern California study with a margin of error of 4.9%.<span>
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The solution would be like this for this specific problem:
Volume of a cylinder = pi * r^2 * h
Volume of a cone = 1/3 * pi * r^2 * h
Total Height = 47
Height of the cone = 12
Height of the cylinder = 35
If the top half is filled with sand, then:
volume (sand) = pi * 4^2 * 36
volume (cone) = 1/3 * pi * 4^2 * 12
Total volume = 1960.353816 cubic millimeters
353816 / (10 * pi) = 62.4 seconds.
It will take 62.4 seconds until all of the sand has dripped to the bottom of the hourglass.
Not to good with math but the answer may be B
Answer:
53 divided by 12 is 4.4167
Step-by-step explanation:
