This Math Problem for 8-Year-Olds Left Parents Stumped

iStock
iStock

Life for grade-schoolers has changed a lot in just a few decades. While students growing up in the pre-digital age had to suffer through insanely difficult homework in silence, kids (and their parents) today can share their frustrations on the internet.

According to Over Sixty, the latest assignment to go viral comes from the parenting message board Mumsnet. After posting their 8-year-old child's math homework on a forum, user lucysmam quickly saw that the other parents were just as baffled by it. Here's the problem:

“On the coast there are three lighthouses. The first light shines for 3 seconds, then it is off for 3 seconds. The second light shines for 4 seconds, then it is off for 4 seconds. The third light shines for 5 seconds, then it is off for 5 seconds. All three lights have just come on together.

When is the first time that all three of the lights will be off together?

When is the next time that all three lights will come on at exactly the same moment?”

Give up? The answer the parents came up with was 6 seconds for the first question and 120 seconds for the second one. The question becomes easier when you think of the lighthouses this way: The first one lights up every 6 seconds, the second one lights up every 8 seconds, and the third one lights up every 10 seconds. To calculate when all the lights will coincide, you need to find the lowest number divisible by six, eight, and 10, which comes out to 120.

When it comes to head-scratching elementary school lessons, this problem is just the start. If this viral problem is any indication, 6-year-olds have it even worse than 8-year-olds.

[h/t Over Sixty]

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Plano, Texas Is Home to a Dog-Friendly Movie Theater That Serves Bottomless Wine or Whiskey

K9 Cinemas
K9 Cinemas

For dog owners in Plano, Texas, movie night with Fido no longer just means cuddling on the couch and browsing Netflix. The recently opened K9 Cinemas invites moviegoers—both human and canine—to watch classic films on the big screen. And the best part for the human members of this couple? Your $15 ticket includes bottomless wine or whiskey (or soft drinks if you're under 21).

The theater operates as a pop-up (or perhaps pup-up?) in a private event space near Custer Road and 15th Street in Plano. Snacks—both the pet and people kind—are available for $2 apiece. Dogs are limited to two per person, and just 25 human seats are sold per showing to leave room for the furry guests.

Pet owners are asked follow a few rules in order to take advantage of what the theater has to offer. Dogs must be up-to-date on all their shots, and owners can submit veterinary records online or bring a hard copy to the theater to verify their pooch's health status. Once inside, owners are responsible for taking their dog out for potty breaks and cleaning up after any accidents that happen (thankfully the floors are concrete and easy to wipe down).

While many of the movies shown are canine-themed—a recent screening of A Dog's Journey included branded bandanas with every ticket purchase—they also hold special events, like a Game of Thrones finale watch party (no word on how the puppers in attendance responded to Jon Snow finally acknowledging what a good boy Ghost is).

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