1, write directly.
42×20= 240÷5= 700×40= 707÷7= 60× 12=
9600÷8= 30×62= 340÷4= 14×7= 8 10÷90=
2. Column vertical calculation.
178×46= 408×25= 37×235= 380×23=
3. Calculate with recursive equation.
360÷6×5 1 380+350÷70 ( 165-75÷3)×8
4 1, the number is written directly:
①30× 12= ②23×4= ③540-3 10= ④4× 140= ⑤630+70=
⑥ 130×20= ⑦ 180×5= ⑧ 170×5= ⑨500×5= ⑩2 10÷7=
2, with vertical calculation:
⑴ 236×43= ⑵ 208×56=
⑶ 720×42= ⑷ 480×50=
1, a number written directly.
85÷ 17= 950÷ 19= 144÷ 12= 63÷2 1= 780÷ 13= 630÷2 1=
75÷ 15= 240÷ 15= 380÷ 19= 520÷26= 420÷2 1= 80÷ 16=
200÷25= 500÷25= 400÷25= 1000÷25= 225÷25= 750÷25=
140÷20= 360÷ 18= 630÷70= 95÷ 19= 270÷90= 360÷ 12=
2. Column vertical calculation.
5 16÷43= 279÷93= 888÷74=
3, column recursive equation calculation.
1000-(480÷96+36) 253+(565-205)÷30 375÷(25- 10)× 15
1, the number is written directly:
①39÷3= ②80÷20= ③640÷80= ④800÷400= ⑤240÷60=
⑥20×5= ⑦270÷90= ⑧570÷3= ⑨3500÷700= ⑩900÷ 100=
2. Estimate:
①80÷ 19≈ ②92÷30≈ ③400÷49≈ ④632÷90≈
⑤633÷88≈ ⑥350÷68≈ ⑦242÷60≈ ⑧240÷8 1≈
3, with vertical calculation:
①720÷ 18= ②432÷27= ③958÷43= ④708÷59=
1, happy oral arithmetic. (10)
80÷20= 140÷70= 450÷50= 240÷30= 360÷6=
25×4= 240×3= 200×30= 180×5= 60× 120=
2. Calculate the following questions vertically. (12)
( 1)285×24= (2) 208× 15= (3) 32× 130=
(4) 130×60= (5) 702÷ 13= (6) 278÷73=
3. Estimate the following questions. (4 points)
( 1)722÷90≈ (2)36 1÷59≈ (3)208×29≈ (4)49×79≈
4. Column calculation. (4 points)
(1) One factor is 298 and the other factor is 3 1. What is the approximate product?
(2) It is known that the product of two factors is 576, and one factor is 18. What is another factor?