Solution
When multiplying by 9, subtract your digit by 1 to get the tens digit.
So 6 - 1 = 5.
The sum of the digits in your answer adds up to 9. So if the tens digit is 5, then the ones digit is 9 - 5 = 4.
Therefore, your answer is 54
Alternate strategy: When multiplying by 9, just multiply by 10 and subtract
the number. In this case, we have
6 × 9 =
6 × 10 - 6 =
60 - 6 =
54
Alternate strategy: Put both hands in front of you with all 10 fingers out. Take finger #6 and curl it. You'll see 5 fingers to your left and 4 fingers to your right. See how this gives you the answer of 54? |
