Question 452272: A cyclist can ride from A to B and back in a certain time at an average rate of 10 km an hour. If he were to ride from A to B at 9km an hour, vand return at 12km an hour, he would save 15 minutes on the double journey. Find the distance from a to B.
A man buys apples at $6 a dozen, and twice as many at $9 a score; he sells them at $9 a dozen, and make a profit of $102. How many apples does he buy?
A man bought a number of eggs at four for $1, and four times as many at five for $1.50; he sells them at a penny each, and make a profit of $44. How many eggs does he buy?
I want the equation of these question(no solution is OK), please~~ in hurry
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A cyclist can ride from A to B and back in a certain time at an average rate of 10 km an hour.
If he were to ride from A to B at 9km an hour, and return at 12km an hour, he would save 15 minutes on the double journey.
Find the distance from a to B.
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Change 15 min to  hrs
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Let d = dist from A to B
then
2d = round trip dist
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 = original time for round trip
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 +  = his "If" time for the round trip
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"If" time + 15 min = original time
+ + =
Multiply by 180 to clear the denominators, solve for d
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A man buys apples at $6 a dozen, and twice as many at $9 a score; he sells them at $9 a dozen, and make a profit of $102.
How many apples does he buy?
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Let x = no. of apples bought at $6/12 or .50 ea
then
(2x) = no. of apples bought at $9/20 or .45 ea
therefore:
.50x + .45(2x) = 1.4x total cost of apples
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3x = no. of apples sold at $9/12 or .75 ea
therefore
3x(.75) = $2.25x, total revenue from the apples
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Rev - cost = profit
2.25x - 1.4x = $102
solve for x, remember he bought a total of 3x apples
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A man bought a number of eggs at four for $1, and four times as many at five for $1.50; he sells them at a penny each, and make a profit of $44.
How many eggs does he buy?
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This does not make sense
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You are buying at .25 ea and selling for .01 ea, will not make a profit
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You have to clarify this
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