- #1
novae
- 15
- 1
Homework Statement
** sorry, answer in the book doesn't make sense **
A british concord and a French concord flew in opposite directions around the world, a distance of 40K km. The BC covered half its distance at 2500 km/h, and the other half at 1000km/h. The FC spent half its flight time at 2500 km/h and the other half at 1000 km/h. Which concorde completed the trip first and by how many hours did it beat the oher?
Homework Equations
V= d/t.
The Attempt at a Solution
Time for BC [/B]
20 000km /t = 2500
t= 20 000/2500
t= 8 hours
20 000km/1000=t
20 hrs = t
Total time = 28 hours
Time for FC
40 000 = 2500 (t/2) + 1000 (t/2)
40 000 = 3500 (t/2)
(40 000/3500)2= t
22.9 hours =t
Looking at this, the french concorde got there first and beat the British concord by 5.1 hours. At the back, the difference I got is correct, it is 5.1 hours, but it says the British concord got there first. How? The BC trip was 28 hours, the FC trip was 22.9 unless I did something wrong ?
*I'm sorry this is probably a dumb question, but I don't remember if my teacher said the answer at the back was incorrect or not, so this is me reconfirming my assumption that the book is wrong *