MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
Grade: 12th Pass
        An aeroplane lefts 30 minute later than it's shedule time and in order to reach its destination 1500 km away in time. It had to increase its speed by 250 km/hr. from its usual speed. Determine its usual time.
8 years ago

Answers : (1)

Sudheesh Singanamalla
114 Points
							

Let the usual speed of the plane be 'x' hours

Time taken to cover 1500km with usual speed = 1500/x hrs

time taken to cover 1500km with speed of (x+250) = 1500/(x+250) hrs

1500/x = 1500/(x+250) + 1/2

1500/x - 1500/(x+250) = 1/2

1500x + 1500*250 - 1500x / (x*(x+250)) = 1/2

1500*250 / x2+250x = 1/2

750000 = x2 + 250x

x2+250x - 750000 = 0

x2 + 1000x - 750x - 750000 = 0

x ( x+1000) - 750 (x+1000) =0

(x+1000)(x-750) = 0

which means x = -1000 , which is not possible , as speed cannot be negative

or x = 750

so the usual speed of the plane is 750 kmph

usual time = distance / speed = 1500 / 750 = 150/75 = 2 hours !

 

Please approve !

8 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details