1. ten by ten:
formulas: the head by head,
lady gaga heartbeats, tail plus tail, tail by tail.
Example: 12 × 14 =?
solution: 1 × 1 = 1
2 +4 = 6
2 × 4 = 8
12 × 14 = 168
Note: a bit multiply, not use the 0 digit placeholder.
2. head the same, complementary tail (tail add up to 10):
formulas: a first add 1 to the head by head, tail by tail.
Example: 23 × 27 =?
Solution: 2 +1 = 3
2 × 3 = 6
3 × 7 = 21
23 × 27 = 621
Note: a bit multiply,
monster beats dr dre, not use the 0 digit placeholder.
3. complementary first multiplier, the same as the other multiplier:
formulas: a first add 1 to the head by head, tail by tail.
Example: 37 × 44 =?
solution: 3 +1 = 4
4 × 4 = 16
7 × 4 = 28
; 37 × 44 = 1628
Note: a bit multiply,
beats by dre studio, not use the 0 digit placeholder.
4. dozens of dozens of one by one:
formulas: head by head, head plus head, tail by tail.
Example: 21 × 41 =?
solutions: 2 × 4 = 8
2 +4 = 6
1 × 1 = 1
; 21 × 41 = 861
5.11 by any number:
formulas: sum of fixed fate,
monster beats by dre, and the middle of the drop-down.
Example: 11 × 23125 =?
Solution: 2 +3 = 5
3 +1 = 4
1 +2 = 3
; 2 +5 = 7
2 and 5, respectively,
beats by dr dre studio, in the sum of
11 × 23125 = 254375
Note: and over ten to get into one.
6. dozen by any number:
formulas: Second Take is not the first fate of several trends,
dr dre headphones, the first digit multiplied by the factor behind the second factor of each number, plus the next digit, again missing.
Example: 13 × 326 =?
solution: 13 bits is 3
3 × 3 +2 = 11
3 × 2 +6 = 12
; 3 × 6 = 18
13 × 326 = 4238
Note: and over ten to get into one.