Question

a plane started late by 30 minutes. to reach a destination 1500 km away in time the piolet increased the speed by 100km/hr. then find the original speed of the plane

Answer 1

time =30/60=1/2 hrs,
let original speed be x,
then orig.time=1500/x;
now when speed increases,
new time =1500/x+10;
now,
equation is,
1500/x + 30=1500/x+10;
solve this equation to get your answer...
if answer helps you.. please mark as brainliest

Answer 2

Answer:

Step-by-step explanation:

Let the Original speed of the aeroplane be x km/h.

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

Time taken to cover 1500 km with the increase speed of (x+100) km/h = 1500 / (x+100) hrs

ATQ

1500 / x = 1500 / (x+100) + ½

1500 / x -  1500 / (x+100) = ½

1500(x+100) -1500x / x(x+100)= ½

1500x + 1500 × 100 -1500x / x² +100x = ½

1500 × 100 / x² +100x = ½

2(1500 × 100 ) = x² + 100x

300000 = x² +100x

x² +100x - 300000 =0

x² -  500 x  + 600 x - 300000= 0

x(x - 500) + 600(x - 500)= 0

(x+600)  (x - 500) = 0

(x+600)  = 0  or  (x - 500) = 0

x = -600  or  x = 500

Speed cannot be negative, so x = 500

Hence the usual speed of the plane is 500 km/h.