The race is on!

Posted by: CanukDenis

The race is on! - 01/24/13 11:44 AM

Li'l cutie I found; here tizz, exactly as I found it:

A slug and a snail planned a race between two stones set a distance D cm apart.

Said the slug to the snail "Since I'm slimier than you, I intend to start T seconds before you".

"In that case", said the snail, who was rather slow, "I'm going to give you X cm start".

It didn't matter. The slug, who could move at speed V cm/s, was only half as fast as the snail.

The result was a dead heat, t seconds after the slug set off.

D, t, T, V and X are whole numbers from 1 to 10 inclusive, no two numbers being the same.

How long did it take the snail to reach the finish?

Posted by: CCbomber

Re: The race is on! - 01/25/13 05:41 AM

distance the slug travels = D-X = Vt
distance the snail travels = D = 2V(t-T)

time for the snail to finish = t-T = D/2V = (Vt+X)/2V

Starting out with these possibilities,
D = 2,4,6,8,or 10 and
V = 1,2,4,or 5

All can be eliminated except for D=10 and V=1
with t,X,T = 8,2,3 or t,X,T = 7,3,2

In either case, t-T = 5 sec

smile happydance
Posted by: CanukDenis

Re: The race is on! - 01/25/13 11:49 AM

That's what I got too.

..Slug@v[-----x + Tv-----].......D/2...........>

Snail@2v......................D.........................>

Since Snail's speed = twice Slug's, then once
Snail gets going, will travel twice Slug's distance.

Therefore the "x ahead" plus the "T time advantage"
puts the Slug at halfway point when Snail gets going.

Thanks CC.