Later, I just remembered the formula. Children's mathematics is very important for basic skills, and it is also the basis for learning mathematics well in the future. These must be followed up!
The method of teaching addition:
1. Tell him the number first, 1- 100, and memorize it;
2. Tell him1+1= 2;
3. Then prove to him that 1 small pieces of paper and small pieces of paper are one or two pieces of paper.
Let him teach himself the above three steps, and then leave it alone.
Parents, don't rush it. Tell it a story at night. The story changes the plot and inserts a short formula table. Before telling the story the next night, review what the mermaid princess read the day before yesterday. The prince appeared. This is interest.
10 internal addition formula table
1+ 1= 2
1+ 2= 3 2+ 2= 4
1+ 3= 4 2+ 3= 5 3+ 3= 6
1+ 4= 5 2+ 4= 6 3+ 4= 7 4+ 4= 8
1+ 5= 6 2+ 5= 7 3+ 5= 8 4+ 5= 9 5+ 5= 10
1+ 6= 7 2+ 6= 8 3+ 6= 9 4+ 6= 10 5+ 6= 1 1 6+ 6= 12
1+ 7= 8 2+ 7= 9 3+ 7= 10 4+ 7= 1 1 5+ 7= 12 6+ 7= 13 7+ 7= 14
1+ 8= 9 2+ 8= 10 3+ 8= 1 1 4+ 8= 12 5+ 8= 13 6+ 8= 14 7+ 8= 15 8+ 8= 16
1+ 9= 10 2+ 9= 1 1 3+ 9= 12 4+ 9= 13 5+ 9= 14 6+ 9= 15 7+ 9= 16 8+ 9= 17 9+ 9= 18
Add the formula within 20 minutes.
1+ 1 1= 12 2+ 1 1= 13 3+ 1 1= 14 4+ 1 1= 15 5+ 1 / kloc-0/= 16 6+6 5438+0 1= 17 7+ 1 1= 18 8+ 1 1= 19 9+ 1 1=20
1+ 12= 13 2+ 12= 14 3+ 12= 15 4+ 12= 16 5+ 12= 17 6+ 12= 18 7+ 12= 19 8+ 12=20
1+ 13= 14 2+ 13= 15 3+ 13= 16 4+ 13= 17 5+ 13= 18 6+ 13= 19 7+ 13=20
1+ 14= 15 2+ 14= 16 3+ 14= 17 4+ 14= 18 5+ 14= 19 6+ 14=20
1+ 15= 16 2+ 15= 17 3+ 15= 18 4+ 15= 19 5+ 15=20
1+ 16= 17 2+ 16= 18 3+ 16= 19 4+ 16=20
1+ 17= 18 2+ 17= 19 3+ 17=20
1+ 18= 19 2+ 18=20
19+ 1=20
1× 1= 1 1×2=2 1×3=3 1×4=4 1×5=5 1×6=6 1×7=7 1×8=8 1×9=9 1 × 10= 10 65438 +0× 1 1= 1 1 1× 12= 12 1× 13= 13 1× / kloc-0/4= 14 1× 15= 15 1×65438+ 06= 16 1× 17= 17 1× 18= 18 1× 19= 19
Twice the multiplication is:
2×2=4 2×3=6 2×4=8 2×5= 10 2×6= 12 2×7= 14 2×8= 16 2×9= 18 2× 10=20 2× 1 1=22 2× 1 2=24 2× 13=26 2×6543 8+04=28 2× 15=30 2× 16=32 2× 17=34 2× 18=36 2× 19=38
The multiplication of 3 times is:
3×3=9 3×4= 12 3×5= 15 3×6= 18 3×7=2 1 3×8=24 3×9=27 3× 10=30 3× 1 1=33 3× 12=36 3× 1 3=39 3× 14=42 3×6 5438+05=45 3× 16=48 3× 17=5 1 3× 18=54 3× 19=57
The multiplication of 4 times is:
4×4= 16 4×5=20 4×6=24 4×7=28 4×8=32 4×9=36 4× 10=40 4× 1 1=44 4× 12=48 4× 13=52 4× 14=56 4× 1 5=60 4× 16=64 4× 17=68 4× 18=72 4× 19=76
The multiplication operation of 5 times is:
5×5=25 5×6=30 5×7=35 5×8=40 5×9=45 5× 10=50 5× 1 1=55 5× 12=60 5× 13=65 5× 14=70 5× 15=75 5× 1 6=80 5× 17=85 5× 18=90 5× 19=95
The multiplication operation of 6 times is:
6×6=36 6×7=42 6×8=48 6×9=54 6× 10=60 6× 1 1=66 6× 12=72 6× 13=78 6× 14=84 6× 15=90 6× 1 6=96 6× 17= 102 6× 18= 108 6× 19= 1 14
The multiplication operation of 7 times is:
7×7=49 7×8=56 7×9=63 7× 10=70 7× 1 1=77 7× 12=84 7× 13=9 1 7× 14=98 7× 15= 105 7× / kloc-0/6= 1 12 7× 17= 1 19 7× 18= 126 7× 19= 133
Eight times the multiplication is:
8×8=64 8×9=72 8× 10=80 8× 1 1=88 8× 12=96 8× 13= 104 8× 14= 1 12 8× 15= 1 20 8× 16= 128 8× 17= 136 8× 18= 144 8× 19= 152
The multiplication operation of 9 times is:
9×9=8 1 9× 10=90 9× 1 1=99 9× 12= 108 9× 13= 1 17 9× 14= 126 9× 1 5= 135 9× 16=654 38+044 9× 17= 153 9× 18= 162 9× 19= 17 1
10 is multiplied by:
10× 10= 100 10× 1 1= 1 10 10× 12= 120 10× 13= 1 30 10× 14= 140 10× 15= 150 10× 16= 160 10× 17= 170 1 0× 18= 180 10× 19= 190
1 1 is multiplied as follows:
1 1× 1 1= 12 1 1 1× 12= 132 1 1× 13= 143 1 1× 14= 154 654 38+0 1× 15= 165 1 1× 16= 176 1 1× 17= / kloc-0/87 1 1× 18= 198 1 1× 19=209
12 is multiplied by:
12× 12= 144 12× 13= 156 12× 14= 168 12× 15= 180 12× / kloc-0/6= 192 12×65 438+07=204 12× 18=2 16 12× 19=228
13 is multiplied by:
13× 13= 169 13× 14= 182 13× 15= 195 13× 16=208 13× 1 7=22 1 13× 18=234 13× 19=247
14 is multiplied by:
14× 14= 196 14× 15=2 10 14× 16=224 14× 17=238 14× 18=252 14× 19=266
15 is multiplied by:
15× 15=225 15× 16=240 15× 17=255 15× 18=270 15× 19=285
16 is multiplied by:
16× 16=256 16× 17=272 16× 18=288 16× 19=304
17 is multiplied by:
17× 17=289 17× 18=306 17× 19=323
18 is multiplied by:
18× 18=324 18× 19=342
19 is multiplied by:
19× 19=36 1
Abacus mental arithmetic formula table
Addition formula table
Direct addition of items/formulas
Add (at most) to the last five.
(Next five to several) Add ten.
(Go to several places and enter several places) Add it to five places and enter ten places.
(Up and down several times, five into one)
One, one, one, one, five, four, one, nine and one.
Two, two, two, two, five, three, two, eight, one.
Three, three, three, three, five, two, three, seven, one.
Four, four, four, four, five, one, four, six, one.
Five, five, five, five, one.
Six, six, six, six, four, one, one, five.
Seven, seven, seven, seven, three in one, seven in two, five in one.
Eight, eight, eight, eight, two in one, eight in three, five in one.
Nine, nine, nine, go, one in, one in, four in, five in, one in.
Subtraction formula table
Carry subtraction without carry addition and subtraction
Direct subtraction
Subtract five (times)
(Up and down, to five) Subtract directly from ten.
(Several times) Borrow (return) ten to make up five subtraction.
(Go back several times, come back five times)
One walk, one walk, one walk, four walk, one walk, one time, nine times.
Two, two, two, three, five, two, one, eight.
Three, three, three, up, two, five, three, backward and seven.
Four to four, four to four, one to four, one to five, one to six.
Five to five, five to five, one to five.
Six to six, six to one, four to six, one to five, one to one.
Seven to seven, seven to retreat, one to three to seven, one to five to two.
Eight to eight, one to eight, one to two to eight, one to five to three.
Nine to nine, one to one, one to one, five to four.