Lori solved this multiplication problem. 29 * 31 = 699 However, the mistake Lori made when multiplying is that she didn't

First we set up the long multiplication

Next we multiply 1 * 9 which is 9

Next we multiply 1 * 2 which is 2

Next we multiply 3 * 9 = 27 and s ince 27 is two-digit, we have to carry the first digit 2 to the next column

Next we multiply 3 * 2 which is 6 and then we carry digit of 2, which is 8

And lastly we add 870 + 29 and we get 899.