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GrogVix [38]
3 years ago
11

A car completes a journey at an average speed of 40km/h.At what speed must it travel on the return journey if the average speed

for the complete journey is 60km/h?
Mathematics
1 answer:
nalin [4]3 years ago
5 0
The distance, s = 40t₁ where t₁ is the time to complete the outward journey.
The same distance = vt₂ where t₂ is the time to complete the return journey at speed v.
For the whole journey, 2s=60(t₁+t₂). Therefore s=30(t₁+t₂)=40t₁=vt₂.
30t₁+30t₂=40t₁, 10t₁=30t₂, t₁=3t₂, so s=120t₂=vt₂ and v=120kph.
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irinina [24]

Answer:

60%

Step-by-step explanation:

If I get you right, you're asking for the percentage gain to the nearest percentage, right?

Now to do this, we need to get the amount of profit she made. That's quite easy, we only need to subtract the cost price from the selling price. And that equals $15 - $9.38 that equals $5.62.

Now, we divide this value by the cost price and multiply by 100% to get the percentage gain.

I.e 5.62/9.38 × 100%.

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2 years ago
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Illusion [34]

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3 years ago
Find the diameter of the sphere with the volume of 36 pi cubic units
kobusy [5.1K]

Answer:

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