How much is one and a half times one and a half?

Answer 1

Since halves times halves equal quarters, the answer of a number times itself plus a half will always end in a quarter as in: .25 or ¼.

And to get an answer to any number plus one half times itself, add ONE to the whole number, times the original whole number times that number and add the quarter. Examples:

1½ × 1½ = 2¼ since 1+1=2, it would be 1×2+¼.

2½ × 2½ = 6¼ since 2+1=3, it would be 2×3+¼.

3½ × 4½ = 12¼ since 3+1=4, it would be 3×4+¼.

4½ × 5½ = 20¼ since 4+1=5, it would be 4×5+¼.

5½ × 6½ = 30¼ since 5+1=6, it would be 5×6+¼.

6½ × 7½ = 42¼ since 6+1=7, it would be 6×7+¼.

37½×37½=1,406¼ since 37+1=38, it would be 37×38+¼.

You can do the first several in your head with no pencil or paper. If someone asks you what 6½ times 6½ is, just multiply 6×7 in your head, which equals 42 and add ¼ to it. The answer is: 42¼ or 42.25.

It is always fun to learn little math tricks like that.