‘Tom travels from a to b and at a speed of 90km per hour. It takes him time ‘t’. Alice travels from a to b at a speed of 70km per hour. It takes her time ‘t+ 1 hour’.

How long did it take for Tom to complete his journey?’

Question

‘Tom travels from a to b and at a speed of 90km per hour. It takes him time ‘t’.  Alice travels from a to b at a speed of 70km per hour. It takes her time ‘t+ 1 hour’.

How long did it take for Tom to complete his journey?’

anonymous · Answer

@asnaseer

asnaseer · Answer

Call the distance between a and b 'd'.
This distance does not change.

Now calculate 'd' based on Toms speed and time.
Then calculate 'd' based on Alice's speed and time.

Both values should be equal.
Use this fact to solve for 't' and that should lead you to the answer.

anonymous · Answer

so 3.5

asnaseer · Answer

Please show your steps so that I can spot where you may have made a mistake

anonymous · Answer

90t=70(t+1)
20t=70
t=70/20=3.5 hours

asnaseer · Answer

Oh - ok - that IS correct - I /thought/ you had given the value for distance between a and b :)