Answer: 4.3 miles
The decimal 4.3 is equivalent to the mixed number 4 & 3/10
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Step-by-step explanation:
Fractions are often a pain, so I find it helpful to convert to decimal form whenever possible.
1/2 = 0.5
21 & 1/2 = 21 + 1/2 = 21 + 0.5 = 21.5
21 & 1/2 miles = 21.5 miles
The object travels 21.5 miles in 5 hours. Divide the distance over the time value to get the speed (or rate). This is exactly identical to finding the number of miles traveled in one hour (since each hour the object travels the same amount of distance)
speed = distance/time = 21.5/5 = 4.3 mph
4.3 = 4 + 0.3 = 4 + 3/10 = 4 & 3/10
In my opinion, it is much easier to use decimals. Saying "the object traveled a distance of 4 & 3/10 miles" seems very clunky to me.
Therefore, each hour, the object travels 4.3 miles.