Each digit can be used only once. You can only use digits 1 to 9 (there’s no zero in the calculator). Often, there are more than one correct answer or number combination, and you can use either. From our experience, solving at least 30 problems correctly results in a good score, while solving 40+ correctly is excellent. Digit Challenge Solving Tips The digit “1” can be very useful in questions with multiplication operations. As multiplying by “1” results in the original amount, you can use this digit to render one of the variables redundant. Pay attention to multiplication, which has precedence over addition and subtraction. In questions that have multiplication, remember that a predefined result ending with 5 or 0 is the product of the number 5. Try to estimate the appropriate digit for the equation, such as higher digits for higher predefined results. A number whose sum of digits is divisible by 3 is also divided by 3. Try to break down the result into prime factors in an equation with only multiplications. For example, the prime factors of 15 are 3 and 5 (because 3×5=15, and 3 and 5 are prime numbers). If you don’t remember the multiplication table by heart or want to play it safe, print out a copy of it and place it near you. If you’re making calculations on scratch paper, always avoid using the zero digit, as it doesn’t appear on the test. Digit Challenge Practice Simulations As you’ve seen above, the Digit Challenge gets super challenging quickly. So, it’s a wise idea to practice before diving into the deep water and taking the actual test. From our experience, the best way to prepare for the Digit Challenge and increase your chances of acing it is by using practice simulations. These practice tests look and feel like the real thing and have the same elements that make this assessment so challenging. Specifically, they give you an interactive calculator with 1-9 digits, the same time limit (5 minutes), and the same adaptivity concept (the questions get harder throughout the simulation).