Math Puzzles

-4

How Many Flowers

In a bouquet of flowers, all but two are roses, all but two are tulips, and all but two are daisies. How many flowers are in the bouquet?



-3

Adding Up To 15

How can you place the numbers 1 through 9 in a 3x3 grid such that every row, column, and the two diagonals all add up to 15?


-2

One Equals Two

Consider the following explanation for why 1=2 :

1. Start out   Let y = x
2. Multiply through by x   xy = x2
3. Subtract y2 from each side   xy - y2 = x2 - y2
4. Factor each side   y(x-y) = (x+y)(x-y)
5. Divide both sides by (x-y)   y = x+y
6. Divide both sides by y   y/y = x/y + y/y
7. And so...   1 = x/y + 1
8. Since x=y, x/y = 1   1 = 1 + 1
8. And so...   1 = 2

How is this possible?