( 1)20+20+20=60
Multiplication formula: _ _ _ _ _ _
(2)30+30+30+30= 120
Multiplication formula: _ _ _ _ _ _
(3) 1000+ 1000+ 1000+ 1000+ 1000+ 1000=6000
Multiplication formula: _ _ _ _ _ _
(4)500+500+500+500=2000
Multiplication formula: _ _ _ _ _ _
(5) 120+ 120+ 120+ 120=240
Multiplication formula: _ _ _ _ _ _
2. Rewrite the following multiplication formula into addition formula.
( 1)30×2=60
Addition formula: _ _ _ _ _ _
(2) 100×4=400
Addition formula: _ _ _ _ _ _
(3)23×3=69
Addition formula: _ _ _ _ _ _
(4)2 10×4=840
Addition formula: _ _ _ _ _ _
3. Fill in the blanks.
The expression (1) 120×3 means _ _ _ _ _.
(2)500×6 can be read as _ _ _ _ _ _ _ _, or as _ _ _ _ _.
(3)60 times 2 to write _ _ _ _ _.
(4)3 times 10 to write _ _ _ _ _.
How do you find it easy to multiply a number by a whole ten, a whole hundred and a whole thousand?
5. oral calculation.
4×2=
30×2=
50×3=
40×2=
300×2=
50×3=
400×2=
300×2=
100×7=
200×3=
80×5=
900×7=
400× 1=
60×7=
50×5=
3000×3=
120×4=
24×2=
1 1×8=
3 1×3=
4 1×2=
3×500+7=
10×8+9=
2×8+ 10=
5×6+4=
7×2+8=
12×2+3=
6. Give it a try. Are there any other algorithms?
( 1) 1 10×3=
(2) 120×4=
(3)240×2=
7. Written statement.
(1) The multiplier is 3 and the multiplicand is 120. What is the product?
(2) What is 30 times 8?
(3) What is 5 times 40?
8. Calculate the following questions.
9. Application questions.
(1) Trees are planted on both sides of the school, and 10 trees are planted on each side. A * * *, how many trees are planted?
(2) There are 1 1 white rabbits in Guangming Kindergarten, and the black rabbits are twice as many as the white rabbits. How many black rabbits are there?
(3) A Honda plaid cost 60 cents, and Xiaohua bought 10. How much will it cost?
Answers to oral multiplication exercises
1, omitted
2. Omission
3. What is the sum of (1) three 120? ②500 times 6, and 6 times 500. (3) 60× 2 (4) 10× 3.
4、( 1)60、600、6000 (2)45、450.4500
5. Omission
6. Omission
7、( 1)360 (2)240 (3)2000
8、( 1)2425 (2)65 1 (3)7000 (4)34 13 (5)54 (6)24 (7)42 (8)20
9.( 1)20 trees (2)22 (3)6 yuan