76.
A herring and a half costs a penny and a half; what is the price of a dozen?
77.
What sum of money is in any sense seen to be the double of itself?
COMIC ARITHMETIC
78. At the close of his lecture upon unknown quantities, Dr Bulbous Roots, in playful mood, wrote this puzzle on his blackboard:—
Divide my fifth by my first and you have my fourth; subtract my first from my fifth and you have my second; multiply my first by my fourth followed by my second, and you have my third; place my second after my first and you have my third multiplied by my fourth. What am I?