# Math

Five times the difference of twice a number and three, decreased by the sum of this number and eight, equals thirteen.

# Math

The ages of a father and son add up to 66. The father's age is the son's age reversed. How old could they be?

# Math

Find the four-digit number in which the first digit is one-fourth of the last digit, the second digit is 6 times the first digit, and the third digit is the second digit plus 3.

# Math

If you multiply this number by any other number, the answer will always be zero. What number is this?

# Math

In an alien land far away, half of 10 is 6. If the same proportion holds true, then what is 1/6th of 30 in this alien land?