Solving 16X19 = ? In 2 Seconds

In summary, first do this: 12 + 3 = 15, then 2x3 = 6, then add 150 and 6, you got 156. Take the first number 12, add the ones of the second number -- 3, you got 12 + 3 = 15. Then multiple the ones of the first and second numbers, you got 2x3 = 6.

In summary, first do this: 13 + 5 = 18, then 3x5 = 15, then add 180 and 15, you got 195. Take the first number 13, add the ones from the second number -- 5, you got 13 + 5 = 18. Then multiple the ones of the first and second numbers, you got 3x5 = 15.

In summary, first do this: 17 + 4 = 21, then 7x4 = 28, then add 210 and 28, you got 238. Take the first number 17, add the ones from the second number -- 4, you got 17 + 4 = 21. Then multiple the ones of the first and second numbers, you got 7x4 = 28.

In summary, first do this: 16 + 6 = 22, then 6x6 = 36, then add 220 and 36, you got 256. Take the first number 16, add the ones from the second number -- 6, you got 16 + 6 = 22. Then multiple the ones of the first and second numbers, you got 6x6 = 36.

In summary, first do this: 18 + 9 = 27, then 8x9 = 72, then add 270 and 72, you got 342. Take the first number 18, add the ones from the second number -- 9, you got 18 + 9 = 27. Then multiple the ones of the first and second numbers, you got 8x9 = 72.