A FAMILY IS MOVING AND HAS A NUMBER OF ELECTRONIC DEVISES IN THE SAME BOX ONE BEEPS EVERY 8 MIN.ANOTHER BEEPS EVERY 10 IN.AND THE THIRD DEVISE BEEPS EVERY 12 MIN.IF THEY ALL BEEP TOGETHER AT 3PM. WHAT TIME WILL IT BE WHEN THEY ALL BEEP TOGETHER NEXT?
2006-09-18 14:40:52 · 10 answers · asked by DRU4883 1 in Education & Reference ➔ Higher Education (University +)
5:00 p.m.
The least common multiple of 8, 10, and 12 is 120. 120 minutes = 2 hours.
2006-09-18 14:43:05 · answer #1 · answered by I Know Nuttin 5 · 1⤊ 0⤋
Because one of your numbers is 10, we know that the time will fall on a solid number divisible by 10, which makes things real east to calculate.
8 x 5 = 40
12 x 5= 60
10 x anything= works
So 5 is the first best chance we got.
They beep at 3.
5 beats later and it's 4.00, 3.40
5 more beats and it's 5.00, 4.20
5 more beats and it's 6 and 5, but if one beats at five and the other beats at 5 then the 12 and 8 both beat at 5, and so does the 10, so the answer is:
5pm.
Here's the big question. How fast is this family moving?
If we're crossing time zones, then the times can start to differ drastically.
There isn't enough information to procure a true answer to the "moving" part of the question, so if you think that's important, you better find out the speed of the vehicle.
2006-09-18 14:56:43 · answer #2 · answered by dinochirus 4 · 0⤊ 0⤋
You just have to find a number of minutes that each of those numbers is a factor of. You have 10,8,12. So since 10,8,12 all go into 120, that means every 120 minutes they will all sound together. Since 120 minutes is two hours, if they beep together at 3PM they will do it again two hours later, which is 5PM. That is all it takes. It is just the teacher's clever way of phrasing a common denominator problem so you don't groan from boredom but still do the thinking.
2006-09-18 14:46:16 · answer #3 · answered by Rich Z 7 · 0⤊ 0⤋
8 10 and 12 all share what lowest number as common number....count by 8s ...8, 16, 24, 32, 40 (40 works for 8 and 10 but NOT twelve)..48, 56, 64, 72, 80, 88, 96, 104, 112. 120 (AHHHHHHH.....120 lowest that works for all 3....and 120 is 2 hours so the answer is........5pm.
2006-09-18 14:46:16 · answer #4 · answered by Just_Killing_Time 3 · 0⤊ 0⤋
You have to find the least common factor of 8, 10, and 12....so...that would be 120.
they will all beep two hours later.....at 5pm.
2006-09-18 14:44:05 · answer #5 · answered by frankgrimes.rm 2 · 0⤊ 0⤋
I don't know the answer, but it's definitely not in the 4 or 5 hour... I tried it. If you've got time (it'll obviously take some work), just make three columns of when each will beep and see when they match up.
2006-09-18 14:56:03 · answer #6 · answered by Joelle 1 · 1⤊ 0⤋
I BELIEVE THE ANSWER IS 5:00PM BECAUSE I TRIED DOING THE VARIABLE EQUATION BUT IT DIDNT WORK WHERE I COULD UNDERSTAND IT..SO I DID THE COMMON MULTIPLE OF THE THREE NUMBERS WHICH IS 120...120=2 HOURS...EVERY 2 HOURS, THE BEEPS GO OFF AT THE SAME TIME MEANING THAT IN 2 HOURS FROM 3:00PM, THE BEEPS WILL GO OFF AT THE SAME TIME...WHICH IS 5:00PM..
2006-09-18 14:47:55 · answer #7 · answered by ♥ Miss Brittany ♥ 3 · 1⤊ 0⤋
120 mins or 2 hrs
2006-09-18 14:52:20 · answer #8 · answered by OLUWOLE A 1 · 0⤊ 0⤋
WTF!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! y would wanna know that?
2006-09-18 14:43:01 · answer #9 · answered by Anonymous · 0⤊ 0⤋
um 2+2=4 duh
2006-09-18 14:42:58 · answer #10 · answered by Gangantuan-Megalopolis 2 · 0⤊ 0⤋