Ask Question
10 March, 17:41

Bob and Jack enter a 1000 km bicycle race. Bob cycles 4 km/h faster than Jack, but his bicycle gets a flat tire, which takes 30 minutes to repair. If both of them finish the race in a tie, then how fast was each boy cycling?

+3
Answers (1)
  1. 10 March, 18:26
    0
    Let Jack's speed be x. Bob's is then x + 4.

    Jacks time for the 1000 km is 1000/x.

    Bob's is 1000 / (x+4) + 1/2 (the 1/2 being the 30 minutes he was delayed).

    They tied so their times were equal. 1000/x = 1000 / (x+4) + 1/2.

    We multiply by x (x+4) and get 1000 (x+4) = 1000x + x (x+4) / 2.

    Simplifying, we get x^2 + 4x - 8000 = 0. x = [ - 4 + √ (16 + 32000) ]/2 = √8004 - 2, Jack's speed.

    Bob's will be √8004 + 2.

    This seems way too fast! But I don't see any mistake
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Bob and Jack enter a 1000 km bicycle race. Bob cycles 4 km/h faster than Jack, but his bicycle gets a flat tire, which takes 30 minutes to ...” in 📗 Mathematics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers