The ‘4’ button on my calculator is spoilt, so I cannot enter numbers which contain the digit 4. Moreover, my calculator does not display the digit 4 if 4 is part of an answer either. Thus I cannot enter the calculation 3×24 and do not attempt to do so. Also, the result of multiplying 3 by 18 is displayed as 5 instead of 54 and the result of multiplying 6 by 8 is displayed as 8 instead of 48. If I multiply a positive one-digit number by a positive two-digit number on my calculator and it displays 26, how many possibilities could I have multiplied?
Answer:
6
- The possible results when a positive 1−digit number is multiplied by a positive 2−digit number that will display 26 is 26,426,246, and 264.
- 26=2×13,1×26426=6×71246=3×82264=3×88,8×33
- Hence, there are 6 such possibilities.