Make a Number Smaller than 731 (SOLUTION)

The 7 here is made of two sticks: a short one on top and a long one going down. Take away the top stick and the long one on its own reads as a 1.

Smallest answer: −131. Lay the 7's top stick flat in front of the number as a minus sign. The 7 becomes a 1, so the matchsticks now read −131. Any negative number is smaller than 731, and no other single move makes a smaller one.

Without a minus sign: 137. Put the 7's top stick on top of the last 1 instead. The first digit becomes 1 and the last becomes 7, giving 137, the smallest positive number you can make.

Easiest move: 721. Slide the 3's lower-right stick over to the lower left. The 3 becomes a 2, giving 721.

Other moves work too: put the 7's top stick on the 3 as its upper-left side to make a 9 (191), or lay the last 1 flat in front as a minus sign (−73). Every other single move gives a bigger number (for example 751, by turning the 3 into a 5) or leaves a shape that is not a digit.

Check out the puzzle (without the solution) by clicking here!