Overview: 3 questions will be solved this time.Among them
           ☆1 arithmetic calculations
           ☆2 integer calculations

[1/3 Integer column vertical calculation]
    Question type: Integer division
    Original question: 111111111÷9
    Solution:
    111111111÷9 = 12345679
    Column vertical calculation:

			1	2	3	4	5	6	7	9
9	丿	1	1	1	1	1	1	1	1	1
			9
			2	1
			1	8
				3	1
				2	7
					4	1
					3	6
						5	1
						4	5
							6	1
							5	4
								7	1
								6	3
									8	1
									8	1
										0

[2/3 Integer column vertical calculation]
    Question type: Integer multiplication
    Original question: 266666666×666666667
    Solution:
    266666666×666666667 = 177777777422222222
    Column vertical calculation:

														2	6	6	6	6	6	6	6	6
✖														6	6	6	6	6	6	6	6	7
													1	8	6	6	6	6	6	6	6	2
												1	5	9	9	9	9	9	9	9	6
											1	5	9	9	9	9	9	9	9	6
										1	5	9	9	9	9	9	9	9	6
									1	5	9	9	9	9	9	9	9	6
								1	5	9	9	9	9	9	9	9	6
							1	5	9	9	9	9	9	9	9	6
						1	5	9	9	9	9	9	9	9	6
					1	5	9	9	9	9	9	9	9	6
					1	7	7	7	7	7	7	7	7	4	2	2	2	2	2	2	2	2

[3/3 Formula]
    Work: Calculate the value of equation 1×2+2×3+3×4+4×5+5×6+6×7+7×8+8×9+9×10 .
    Question type: Mathematical calculation
    Solution:
          1×2+2×3+3×4+4×5+5×6+6×7+7×8+8×9+9×10
        =2+2×3+3×4+4×5+5×6+6×7+7×8+8×9+9×10
        =2+6+3×4+4×5+5×6+6×7+7×8+8×9+9×10
        =2+6+12+4×5+5×6+6×7+7×8+8×9+9×10
        =2+6+12+20+5×6+6×7+7×8+8×9+9×10
        =2+6+12+20+30+6×7+7×8+8×9+9×10
        =2+6+12+20+30+42+7×8+8×9+9×10
        =2+6+12+20+30+42+56+8×9+9×10
        =2+6+12+20+30+42+56+72+9×10
        =2+6+12+20+30+42+56+72+90
        =8+12+20+30+42+56+72+90
        =20+20+30+42+56+72+90
        =40+30+42+56+72+90
        =70+42+56+72+90
        =112+56+72+90
        =168+72+90
        =240+90
        =330
    Answer:1×2+2×3+3×4+4×5+5×6+6×7+7×8+8×9+9×10=330

Your problem has not been solved here? Please go to the Hot Problems section！