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3 years ago

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A person, who decided to go to weekend trip should not exceed 8 hours driving in a day. Average speed of forward journey is 60 k

m/h. Due to traffic in Sundays, the return journey average speed is 50 km/h. How far can he select a picnic spot?

1 answer:

Paraphin [41]3 years ago

5 0

Since he must not exceed 8 hours driving in a day:
Let the distance of the picnic be = x km.

Therefore time for forward journey = x / 60
Return journey    = x / 50

The total trip should not exceed 8 hours.
Therefore: x / 60 + x / 50 <= 8.    LCM = 300

Taking LCM and multiplying on both sides:
5x + 6x <= 8(300)
   11x <= 2400
   x <= 2400/11
   x   <= 218.18
The picnic spot must be less than or equal to 218.18 km.

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