1. Ones make ten23 x 271. Ones make tenConfirm the ones add to ten.13 + 7 = 1022 x 3 = 63append 21 -> 621Confirm the ones add to ten.Confirm the ones add to ten.
2. Prefix product23 x 272. Prefix productMultiply tens by next tens.13 + 7 = 1022 x 3 = 63append 21 -> 621Multiply tens by next tens.Multiply tens by next tens.
3. Append ones23 x 273. Append onesAppend the ones product.13 + 7 = 1022 x 3 = 63append 21 -> 621Append the ones product.Append the ones product.