How many threepence equal a dollar?

Answer 1

None.

A Threepence represented three Pennies in the various British based predecimal currencies.

There were 240 predecimal Pennies in a predecimal Pound, so there were 80 Threepences in a predecimal Pound.

At the time of Britains changeover to decimal currency in 1971, the old redundant Threepence became the equivalent of 1.25 New Pence.

There are 100 New Pence in the British decimal Pound.