2.Two bicycles depart from Miami Beach going in opposite directions. The first bicycle is traveling at
10 miles per hour. The second bicycle travels at 5 miles per hour. How long does it take until the bikes are 45 miles apart? (2 points)

Question

2.Two bicycles depart from Miami Beach going in opposite directions. The first bicycle is traveling at 
10 miles per hour.  The second bicycle travels at 5 miles per hour. How long does it take until the bikes are 45 miles apart?  (2 points)

ganeshie8 · Answer

distance = time * speed
=> 45 = t (10 + 5)
=> t = 3 hours

anonymous · Answer

Thanks !

ganeshie8 · Answer

np :)

did u get why we added the speeds, and not subtracted... ?

anonymous · Answer

Because you're trying to figure how long it will take both(meaning add) to reach 45 miles apart right ? Then you divided 45 and 15 I think

ganeshie8 · Answer

yep !!

ganeshie8 · Answer

if they are travelling in same direction.. we have to subtract. since one guy is trying to increase the distance between them, and the other guy is chasing after him, decreasing the distance.

anonymous · Answer

Oh ok that makes a lot more sense .