a plane left 30 minutes late than its scheduled time and in order to reach the destination 1500 km away in time it had to increase the speed by 100 km per hour from the user list speed find the usual speed.
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let the usual speed of plane be x km/hr.
according to the ques
1500/x-1500/x+100=30/60
formula used above is time=distance/speed
1500x+150000-1500x/x^2+100x=1/2
300000=x^2+100x
x^2+100x-300000=0
x^2+600x-500x+300000=0
x(x+600)-500(x+600)=0
(x+600)(x-500)=0
x= -600, 500
since speed cannot be negative x= -600 will not be considered.
therefore x=500km/hr
hope it helps
plz mark it as the brainliest
according to the ques
1500/x-1500/x+100=30/60
formula used above is time=distance/speed
1500x+150000-1500x/x^2+100x=1/2
300000=x^2+100x
x^2+100x-300000=0
x^2+600x-500x+300000=0
x(x+600)-500(x+600)=0
(x+600)(x-500)=0
x= -600, 500
since speed cannot be negative x= -600 will not be considered.
therefore x=500km/hr
hope it helps
plz mark it as the brainliest
Answered by
0
Solution :-
Let the original speed of train be x km/hr
New speed = (x + 100) km/hr
We know that,
Time = Distance / Speed
Given : A plane left 30 minutes or 1/2 hours later than the scheduled time.
According to the question,
=> 1500/x - 1500/(x + 100) = 1/2
=> (1500x + 15000 - 1500x)/x(x + 100) = 1/2
=> 2(15000) = x(x + 100)
=> 30000 = x² + 100x
=> x² + 100x - 30000 = 0
=> x² + 600x - 500x - 30000 = 0
=> x(x + 600) - 500(x + 600) = 0
=> (x - 500) (x + 600) = 0
=> x = 500 or x = - 600
∴ x ≠ - 600 (Because speed can't be negative)
Hence,
Its usual speed = 500 km/hr
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