Elementary arithmetic, with brief notices of its history... by Robert Potts.

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3. If a train 100 yards long pass a fixed object in 5 seconds, at
what rate per hour is the train moving?
4. A fly-wheel revolves once every twenty seconds; how many revolutions does it make in twelve hours?
5. The length of the steps taken by two men are 3 feet and 4 feet,
and the former takes five steps while the latter takes four. If both
started from the same place to walk along the same road, how far
has each walked when one is a hundred feet beyond the other?
6. How long will a column of 10,000 men, marching 4 deep, require
to pass through a defile of 5 miles at the rate of 75 paces of 2 feet
each in one minute, and the column on its march to extend 7500
feet?
7. If sound travel with a velocity of 1100 feet in one second, and
the report of a gun is heard 15 seconds after the appearance of the
flash, how far distant is the observer?
XXX.
1. If the length of the elliptic orbit of the earth round the sun be
596440000 miles, what is the average hourly and daily motion of the
earth, supposing the earth makes one complete revolution in 365%
days?
2. The mean distance of the sun from the earth is about 91,713,000
miles; what is the velocity of light, if the time in which the sun's light
reaches the earth be 8min. 18sec.?
3. What is the difference in the hourly rates of the motion of two
places, caused by the diurnal rotation of the earth on its axis, one on
the equator and the other on the parallel of the latitude of London,
supposing the circumference of these circles to be 24,900 and 15,120
English miles respectively?
4. How many seconds are there in a year of the planet Saturn,
which consists of 10746 days 16min. 15sec. of time, as reckoned at the
earth?
5. How many years of the earth are equivalent to one year of
Uranus, one year of the earth being 365 days 5hrs. 48min. 51sec., and
of Uranus 30688 days 17hrs. 6min. 16sec.?
6. How many of Jupiter's years have elapsed since the birth of
Christ to A.D. 1863, if one year of the earth be 365 days Shrs.
48min. 51sec., and one year of Jupiter be 4330 days 4hrs. 39min.
2sec.?
7. The periodic time, or length of the year of the planet Uranus, is
84 years 5 days 19hrs. 41min. 36sec., and of the earth 365 days
5hrs. 4~min. 57sec. Shew that one year of Uranus is greater than 19,
but less than 20, years of the earth.
8. If Sirius, one of the brightest of the fixed stars, which is probably 592,200 times farther from the earth than the sun, were suddenly extinguished, for how long would it still appear to shine to tho