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Puzzle of the Day

These puzzles are also printed in Eight days a week, a booklet published by the Association of Teachers of Mathematics.

Using the digits of 1999 kept in that order and the operations +, -, x, ÷, and brackets can you make any of the numbers from 1 to 20? (For example 9 is 1x(9+9)-9

Answer: 1+(9-9)÷9=1, 1+(9+9)÷9=3, 1x9-(9÷9)=8, 1+9+9-9=10, 1+9+(9÷9)=11, 1+99÷9=12, 19-(9÷9)=18, 19+9-9=19, 19+(9÷9)=20