SOLUTION: in 6 hours A travels 10 Km more THAN B DOES IN 5 HOURS;AND IN 8 hours B travels 7 Km more than A does in 5 hours.WHAT ARE THE SPEEDS OF A AND B.
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-> SOLUTION: in 6 hours A travels 10 Km more THAN B DOES IN 5 HOURS;AND IN 8 hours B travels 7 Km more than A does in 5 hours.WHAT ARE THE SPEEDS OF A AND B.
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Question 794179: in 6 hours A travels 10 Km more THAN B DOES IN 5 HOURS;AND IN 8 hours B travels 7 Km more than A does in 5 hours.WHAT ARE THE SPEEDS OF A AND B. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Let a = A's speed
Let b = B's
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Write a distance equation for each statement, (Dist = time * speed):
:
In 6 hours A travels 10 Km more THAN B DOES IN 5 HOURS;
6a - 5b = 10
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IN 8 hours B travels 7 Km more than A does in 5 hours.
8b - 5a = 7
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Arrange equations for elimination
6a - 5b = 10
-5a+ 8b = 7
Multiply the 1st equation by 8, the 2nd equation by 5
48a - 40b = 80
-25a + 40b = 35
------------------adding eliminates b find a
23a = 115
a = 115/23
a = 5 km/hr is A's speed
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Find b using the 1st equation
6(5) - 5b = 10
-5b = 10 - 30
-5b = -20
b = -20/-5
b = + 4 km/hr is B's speed
:
:
Check this in the 2nd equation
8(4) - 5(5) = 7
32 - 25 = 7
