How much was a bob worth in bob a job week in the UK?

Officially known as Scout Job Week, "Bob a Job Week" started after WWII in order to encourage young people to help other people. In exchange for a small payment, British Boy Scouts turned their hand to gardening, shopping and household chores from dog walking to window cleaning. It got its nickname from the 1 shilling coin, colloquially known as a "Bob", that the youngsters were paid for completing their good turn.

The "Bob" is certainly not a large sum of money but exactly what it would be worth today is debatable. When England "decimalized" their currency they declared 5 pence to be equivalent to 1 shilling. Inflation has multiplied the currency about 10 fold since then (1949 to 2012) so it could be said that the 1949 1 shilling is equivalent to about 50 of today's pence (about 80 US cents). However, the 1950's shilling was made of 0.18 Troy ounces of sterling silver, the value of which would currently (in late 2012) be about 5 US dollars (about 4 British pounds).