Let x be the rate of the slower bicyclist and
x + 4 be the rate of the faster bicyclist
Since the bicyclists are headed towards opposite directions, the sum of the distances they covered traveling for one hour and 15 minutes should be equal to 40 km based on the given conditions above. This may be expressed as,
(x)(1.25) + (x + 4)(1.25) = 40
Calculating gives x = 14
Thus, the rate of the bicyclists are 14 km/h and 18 km/h.
Scale factor is used by architects or engineers to transfer their prototype idea to large-scale use. If the volume of a prism is 20, you need to multiply its dimensions with a scale factor to find the new volume which is 540. For example, if the volume is doubled, this means you used a scale factor of 2. Hence, you just have to divide the new volume by the smaller volume.
Scale factor = 540/20
Scale factor = 27
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Find the duration
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Time : 9:00am to 10:15am
Duration: 1hour 15 mins or 1.25hours
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Find difference in distance travelled between the two cyclists.
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Difference in speed = 6km/h
1 hour = 6 km
1.25 hours = 7.5km
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Find the distance the cyclist traveled
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42.5 - 7.5 = 35km
35km ÷ 2 = 17.5km
The slower cyclist traveled 17.5 km in the 1.25 hours
17.5 + 7.5 = 25 km
The faster cyclist traveled 25km in the 1.25 hours
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Find the speed of the slower cyclist
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1.25 hour = 17.5 km
1 hour = 17.25 ÷ 1.25
1 hour = 14km
The cyclist was traveling at 14km/h
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Find the speed of the faster cyclist
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1.25 hour = 25km
1 hour = 25 ÷ 1.25
1hour = 20 km
The cyclist was traveling at 20km/hour
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Answer: The speed were 14km/h and 20 km/h
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