Stretch question. A pictogram shows sales of umbrellas over 4 days using a symbol worth 6 umbrellas: Monday 2 symbols, Tuesday 3 and a half symbols, Wednesday 1 symbol, Thursday 4 symbols. Work out the number of umbrellas sold each day, the total sold over the 4 days, and, if Friday's sales were double Thursday's, how many umbrellas were sold on Friday.
(4)