Question

7. CHALLENGE: Use the digits 0 to 9 to make the equation true. You don't need to use all thedigits you can only use each digit once.
20 = ___+(___-___)×___​

Answer 1

9514 1404 393

Answer:

  20 = 2 + (7 -4) × 6

Step-by-step explanation:

The Order of Operations requires the parentheses be evaluated first, then the multiplication performed. Finally, the addition is performed.

If each of the blanks is filled with a single digit, the result of the multiplication must be a composite number greater than 10. Those are 12, 14, 15, 16, 18, 20. For the expression shown above, we have chosen to make the product be 18. That means the first blank is filled with 2 and the remaining blanks must evaluate to one of the products 2×9 or 3×6.

We have chosen 6 for the last blank, so the two blanks in parentheses must have a difference of 3. The digits 2 and 6 cannot be used, leaving possible choices as (3-0), (4-1), (7-4), (8-5).

Our final expression is chosen to be ...

  20 = 2 +(7 -4)×6