Fun Mathy Type Riddles

[GrandizerII]

Let's post some fun mathish riddles. I'll start

In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half of the lake?

Put your answers in hide tags so you don't ruin it for someone else

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Let P be the size of the original patch of lily pads, and L be the size of the lake.

Each day, the patch doubles in size, so a mathematical expression that corresponds to this would be:

P*2^d (where d represents number of days passed)

It takes 48 days for the size of the patch to match the size of the lake (L), so we have an equation as follows:
P*2^48 = L

If we divide both sides of the equation by 2, we get:

P*(2^48)/2 = L/2

P*(2^47) = L/2

L/2 represents half the size of the lake. Therefore, it should take 47 days to cover half the lake.

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Did I get it right?

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A white house is made out of white bricks. A blue house is made out of blue bricks. A yellow house is made out of yellow bricks. A red house is made out of red bricks. What is a green house made of?

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Glass?

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A plane is flying from New York to Ontario. It ends up crashing on the border of the US and Canada. I mean smack dab in the middle of the border, no more in America than it is in Canada. Knowing this which country do you bury the survivors in?

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I'll admit I already knew this one from childhood. Survivors are not dead, so in neither country should they be buried.

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