Girls of a marriageable age do not like to tell how old they are, but
you can find out by following the subjoined instructions, the young lady
doing the figuring: Tell her to put down the number of the month in
which she was born, then to multiply it by 2, then to add 5, then to
multiply it by 50, then to add her age, then to subtract 365, then to
add 115, then tell her to tell you the amount she has left. The two
figures to the right will tell you her age and the remainder the month
of her birth. For example, the amount is 822, she is twenty-two years
old and was born in the eighth month (August).