1x 1= 1
1x2=2 ? 2x2=4
1x3=3 ? 2x3=6 ? 3x3=9
1x4=4 ? 2x4=8 ? 3x4= 12 ? 4x4= 16
1x5=5 ? 2x5= 10 3x5= 15 4x5=20 5x5=25
Formula development
The 99-99 Multiplication Melody is also often called "Little 1999". In ancient times, students learned the formula of "getting one by one" and ending with "10000× 10000", but it was the other way around, starting with "9981" and ending with "one as one". Because the first two words of the formula are "99", people call it "99" for short.
How to help children master multiplication formula quickly;
1, intensive training. Every night, let the children recite a few formulas, such as horizontal back, vertical back and upside down, and train them in different ways. After remembering, let the children do some exercises, such as three twenty-seven, five thirty. Or answer with parents, parents say "four four" and children answer "one sixteen". Or parents say a number, and children say that the product is the formula of this number.
2. Prepare a pair of cards, and make two groups of cards of 1- 10, one for parents and one for children. Two people play cards in turn, and whoever says the product value of the numbers on the two cards first can take the other card. For example, if one person gives 5 and one person gives 2, whoever says "10" first will win the opponent's card. Finally, whoever wins more cards is the winner. Parents can slow down at the beginning to stimulate their children's interest.