Math Prob help

[2001300exguy]

Anyone feel free to help
It is now 6 o'clock. In how many minutes will the minute hand and hour hand form a right angle? The answer is not 9 o'clock.
Thanks for anyone that tries to help

[pro-rider46]

180 min.

[beaker1214]

Originally posted by pro-rider46
180 min.


BINGO

[CaptainCanuck]

6:15-6:20 depending on the angle of the hour hand when it reaches that area.

[beaker1214]

Originally posted by CaptainCanuck
6:15-6:20 depending on the angle of the hour hand when it reaches that area.
dang thats right I didn't read the first post completely

[2001300exguy]

any chance you could show how though? i need to show work for this.

[chris46250r]

Originally posted by 2001300exguy
any chance you could show how though? i need to show work for this.

It's 6:00. 00:15 is the next right angle. 6:00 + 00:15 = 6:15.
6:15 - the original 6:00 = 15 minutes till right angle

[pro-rider46]

dang, i got my hopes up i was smart, thanks alot guys.

[2001300exguy]

its not 6:15 either, the hour hand moves in those 15 minutes so its no longer a perfect angle

[chris46250r]

Originally posted by 2001300exguy
its not 6:15 either, the hour hand moves in those 15 minutes so its no longer a perfect angle

Well screw it then! Tell your teacher you have digital clock.:D

[2001300exguy]

lol ill do that and tell you how it goes

[400exrider99]

its 180 mins

[pro-rider46]

h*ll yeah, i thought i was right, cause i thought about it being wrong cause angle isnt perfect within that 15 mins. just didnt say nuttin.

[chris46250r]

No you are not right either. CaptainCanuck has got it close, but figuring out the exact time I dont have a clue.

[pro-rider46]

i simply give up!

[chris46250r]

Originally posted by pro-rider46
i simply give up!

Me too. Just tell everybody that time is money, here's 20 bucks, dont worry about the time.:devil:

[2001300exguy]

hmm i like that. my teacher said it wasnt 9:00 and it was between 6 and 9. its not an exact time. i have no idea where to even get the formula from

[chris46250r]

Originally posted by 2001300exguy
hmm i like that. my teacher said it wasnt 9:00 and it was between 6 and 9. its not an exact time. i have no idea where to even get the formula from

7:30 +/- 90 minutes.:D

[bwamos]

16 minutes 22 seconds. Use that as a reference so you know if you've got it right nor not. (more accurately 16m 21.82s)

Not going to do the work for you, but you can use ratios to figure it out.

1min = 6deg on the minute hand. 0.5deg on the hour hand.

Mull it out for a while. If you still cant figure it out. I'll help you a bit more until it clicks. ;) Not going to do you and good if I do all the work for you. :)

Remember don't make it too hard. this isn't calculus.

1st step dont worry about time.. You just know you want to get from 180deg to 90deg. Minute hand moves 6deg increments. Hour hand moves 0.5deg increments.

Every minute how much closer does the minute hand come to the hour hand?

Once you figure that out it's easy to figure out how many minutes it takes to get from 180deg to 90deg.

Yes, I'm a nerd. Just incase you were still wondering, lol.

[CaptainCanuck]

Originally posted by 400exrider99
its 180 mins

No its not. I said in between 6:15 and 6:20 because as the minute hand moves, so does the hour hand slowly. As it approaces 6:15, if the hour hand doesnt move, it would form a right angle. But because the hour hand will move slightly, you have to accompansate for the change in angle and go further past 6:15. Draw it out for yourself and see. Just because the angle of the hour hand isn't directly straight across doesn't mean a right angle can be formed from it.

Trust me kid, take my answer. Use a diagram to explain it.

EDIT: Actually, use the guys answer above mine. Its much more precise. I just explained how to get the concept of it. I'm no math head, Im just a Psych major.

[2001300exguy]

Originally posted by bwamos
Remember don't make it too hard. this isn't calculus.

Yeah i figured it out today in physics, thanks. what funny about that is it is for my calc class lol. its just a weekly participation problem. the answer is 16.3636repeating.

[bwamos]

Good deal.

For the sake of the thread here's how I calculated it.

6:00 = 180deg

1min = 360/60 = 6 deg
1hour = 360/12 = 30deg
1min on hour hand = 30/360 = 0.5deg

Every minute the min hand travels 6deg. Hour hand travels 0.5deg.

6deg - 0.5deg = 5.5deg closer each minute.

180deg - 90deg = 90deg.

90deg / (5.5deg/min) = 90deg * (1min/5.5deg) = 16.36363636 minutes

.36363636 min * (60s/min) = 21.818181 seconds

So I ended up with 16min 21.82sec