Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

June 12, 2014

If you like Lego, you might know that helpless feeling when you need a skinny 1-bump-by-4-bump neon green piece, and it MUST be that one piece, and you have to dig through hundreds of pieces to find it. Well, one clever dad has solved our problems. After buying way too many Lego sets for his kids, Ranan Lachman realized we should all just share the same sets, since usually we build that spaceship, castle or flying car only once. His new company, Pley, lets you rent any of 300 Lego sets – which means to pay money to borrow them – and when you’re done you ship the Lego back so someone else can rent it. Since kits might come back missing some pieces, he weighed every single Lego block very exactly, so he can tell what’s missing just by weighing the box. Given that they own over 40 million pieces of Lego, they need to keep track!

Wee ones: If you build 5 Lego Ninjago vehicles and 1 castle, how many kits have you built?

Little kids: This summer Lego will start selling 3 new “girl scientist” kits: a woman astronomer, chemist, and paleontologist (someone who studies fossils like dinosaur bones). If each kit has 100 pieces, how many pieces do you get in total?  Bonus: Pley offers 300 different kits you can borrow. If they double the number of kits this year, how many will they offer then?

Big kids: If one Lego City kit uses 150 pieces and another uses 180 pieces, but 60 of the pieces are the same for the two, how many different pieces do they use together?  Bonus: To rent from Pley you pay a monthly fee. If you sign up from the start of May through the end of December at \$15 per month, how much do you pay in total?

The sky’s the limit: The company owns 40 million pieces of Lego! Assuming it’s 42 million for neat clean math, if that’s spread over 300 styles of kits and every kit uses 200 pieces, how many copies of each kit style can they ship out at once?

Wee ones: 6 kits.

Little kids: 300 pieces.  Bonus: 600 kits.

Big kids: 270 different pieces.  Bonus: \$120, since it’s for 8 full months.

The sky’s the limit: One full set of kits uses 60,000 pieces at once. Then 42 million pieces are enough for 700 copies of every kit!