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

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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]

Learn to Paint Like Bob Ross in an Upcoming Facebook Live Event

Public television hero Bob Ross may no longer be with us, but you can still paint happy little trees in his honor. October 29, 2018 marks what would have been the 76th birthday of the beloved art teacher to the masses, and to honor his memory, the Quarto Group—publisher of the new book Painting With Bob Ross—is hosting a live-streamed painting party online.

Painting With Bob Ross provides step-by-step instructions to help you create some of the master’s favorite oil landscapes on your own. While Quarto’s October 23 painting party (a collaboration with Bob Ross, Inc.) can’t teach you how to mimic Ross's soothing voice, the celebration does include a painting session with Bernie Oropallo, a Certified Ross Instructor, who will demonstrate the techniques that Ross taught on The Joy of Painting.

Promo for The Quarto Group's Bob Ross painting party
The Quarto Group

The live-streamed instructional session will take place within the offices of a youth arts center in Beverly, Massachusetts, called Express Yourself. Oropallo will lead you through the process of painting “Distant Mountains,” one of the artworks included in the new book.

The painting lesson kicks off at 7:30 p.m. ET on October 23. To participate, log onto Facebook and head to the QuartoCreates page to join the live event. Before it starts, check out the event page here for a list of the supplies you’ll need to complete the painting. If you can’t make it to a computer that night, grab Painting With Bob Ross on Amazon ($15) to get the next best thing. If that’s not enough for you, we suggest you curl up with the official Bob Ross art book and/or a Bob Ross coloring book.

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