A girl goes into a supermarket and buys four items. Using a calculator she multiplies the cost (in pounds) instead of adding them.

At the checkout she says, "So that's £7.11" and the checkout man, correctly adding the items, agrees.

What were the prices of the four items?

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This problem is taken from "Sums for Smart Kids" by Laurie Buxton, published by BEAM Education. To obtain a copy call the BEAM orderline on 020 7684 3330. (Price: £13.50 plus handling and delivery.)