The Four Digits Problem
One well-known mathematic problem is to write expressions for the counting numbers beginning with 1.
The rules are:
 Use the digits 1, 2, 3 and 4. Each digit is used only once. All four digits must be used each time.
 You may use addition, subtraction, multiplication (not division), exponents and parentheses in any way
that you wish.
 You may also use two digits to make one number, such as 12 or 43.
Write an expression for each of the following numbers using the digits 1, 2, 3 and 4.
1 = _____________________
18 = _____________________
35 = _____________________
2 = _____________________
19 = _____________________
36 = _____________________
3 = _____________________
20 = _____________________
37 = _____________________
4 = _____________________
21 = _____________________
38 = _____________________
5 = _____________________
22 = _____________________
39 = _____________________
6 = _____________________
23 = _____________________
40 = _____________________
7 = _____________________
24 = _____________________
41 =______________________
8 = _____________________
25 = _____________________
42 = _____________________
9 = _____________________
26 = _____________________
43 = _____________________
10 = _____________________
27 = _____________________
44 = _____________________
11 = _____________________
28 = _____________________
45 = _____________________
12 = _____________________
29 = _____________________
46 = _____________________
13 = _____________________
30 = _____________________
47 = _____________________
14 = _____________________
31 = _____________________
48 = _____________________
15 = _____________________
32 = _____________________
49 = _____________________
16 = _____________________
33 = _____________________
50 = _____________________
17 = _____________________
34 = _____________________
Did using a calculator help you in finding the above expressions? Explain.
Would it make it easier or harder to come up with expressions if you could use division? Explain.
Would it make it easier or harder to come up with expressions if you could not use parentheses? Were the
parentheses helpful? Explain.
Make up your own variation of the Four Digit Problem. Explain your rules, etc. so that someone could follow
your instructions and actually attempt to solve the problem.