The answer is to tick them ALL as they could all be correct -

A: If the pint was 3.5%abv#, the wine 125ml x 9%abv and it was a single whisky that would be 6 units = 3am next morning

B: If the pint was 4%abv, the wine 175ml x 12%abv and it was a single whisky that would be 9 units = 6am next morning

C: If the pint was 5.3%abv, the wine 250ml x 12%abv and it was a double whisky that would be 14units = 11am next morning

D: If the pint was 5.3%abv, the wine 250ml x 15%abv and it was a triple* whisky that would be 18 units = 3pm next afternoon,

UNITs = hours from when you start drinking (9pm in this example)

If you want to be even more safe add an extra hour for good measure (start counting down from 10:00pm).

%abv: percent alcohol by volume = strength. We tend to pour larger measures at home, a single looks so mean!

Remember - 13% of drink-drive convictions are 'morning after', on the way to, or at, work, when the company is legally liable. This is only the tip of the iceberg, it's probably nearer 20%.

Of the 350 people questioned, none got the answer right.

'We would agree with Brake's position that most people don't know strong many drinks are, or when they would be free of alcohol. Having a drink-drive limit is misleading as no-one can tell you what it is, therefore we must work on zero when we drive,' said Roger Singer, head of Avoidd.

'Fleet managers and their drivers need to know the facts to ensure they are alcohol free when at work and/or driving.'