To multiply two 2digit numbers without showing work, first multiply the ones digits together, then 'crossmultiply,' and finally multiply the tens digits together. Make sure to carry whenever a product exceeds 9. As you will see in the examples below, you must work your way from right to left to perform this trick. Example 1: 12 x 23
Example 2: 31 x 24
Note: This trick will also work on numbers with zeroes and decimal points. Also as you are crossmultiplying, it is generally easier to begin with the larger product and then add the smaller product. Comments are closed.

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