Today from Bedtime Math: Paint the Tower Red

The Eiffel Tower, that famously tall, spiky building in Paris, is one of the world's favorite monuments. But the tower, designed by Gustave Eiffel, hasn't always looked the way it does now. Every 7 years the 984-foot tower has to be repainted - not just to make it look beautiful and cool, but also to keep its metal beams from rusting. To make that happen, 25 painters haul out almost 60 tons of paint and miles and miles of safety ropes, and they balance at scary heights to paint the whole tower. Over the years they've mixed things up by changing the color, too. The tower actually started out bright red, then in 1899 painters painted the Tower in 5 fat stripes across it, from yellow-orange at the bottom to light yellow at the top. After many years of boring brown, the Tower switched in 2009 to "bronze"...we'll see if it keeps that color at its next painting.

Now here's today's math~

Wee ones: The Tower is all one shade of bronze now, but it used to be 3 stripes of brown. How many more paint colors did they need to do that? 

Little kids: If the Tower has been red, 4 shades of brown, and 5 shades of yellow, how many different paint colors have been used?  Bonus: If the last time they started painting the Tower was in 2009, when are they due to paint it again if they paint every 7 years? 

Big kids: It takes 18 months to paint the tower. If a round of painting starts in April, in what calendar month do they finish?  Bonus: Those 25 brave painters use 1,500 paint brushes for the project. How many paint brushes does each painter get? 

The sky's the limit: Each round of painting uses about 14,000 gallons of paint. Given that the tower got painted in 1888, then 1889, then again in 1892, and then every 7 years since with just 5 years of delay along the way, how much paint has gone onto the Eiffel Tower so far?

Answers:

Wee ones: 2 more colors.

Little kids: 10 colors.  Bonus: In 2016.

Big kids: In October.  Bonus: 60 brushes per painter. 

The sky's the limit: 1892 to 2009 is a 117-year gap, but should have been just 112 years. At every 7 years, that gives us 16 paintings, plus those first 3 rounds in '88, '89 and '92, giving us 19 total. At 14,000 gallons each, 20 rounds would have been 280,000, so the 19 used 266,000 gallons of paint.