According to the question, Let the original speed of the train be ‘x’ km/h and the original time taken to reach the destination be ‘t’ hours. So, the distance between station ‘P’ and ‘Q’ = x × t = xt km So, xt/(x + 20) = t – 1..........................(1) And, xt/(x + 40) = t – 1 – 0.5 Or, xt/(x + 40) = t – 1.5........................(2) Dividing equation (1) by equation (2), we get (x + 40)/(x + 20) = (t – 1)/(t – 1.5) So, xt – 30 – 5x + 20t = xt + 20t – x – 20 Or, 20t – 5x = 10 Or, x = 4/5 × (20t – 10) Putting the value of ‘x’ in equation (1), we get 40t² – 80t = 40t² – 110t + 70 Or, t = 3 So, x = 4/5 × (60 – 10) = 40 Desired distance = 3 × 40 = 120 km
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A powerful eye irritant present in smog is
Find the odd one:
The element used for making solar cells is
Which of the inert gases can form compounds?
Which of the following processes is used for the production of Biodiesel?
The function of skimming tank in sewage treatment is to remove
