5400 103 180 6
900 960 3 800
Second, use recursive equation to calculate.
(420÷28+ 12)×5= 135
500-(320+320÷4)= 100
480÷80+42× 17=720
Third, solve the problem.
1, 160÷30=5 (architecture) ... 10 (Zhang)
Answer: You can post five math buildings, and there is 10 left.
2,400,000 ÷ 4,000 =1000 (tree)
A: 1 0,000 big trees with wide bowls need to be cut down.
3. (1620-140× 3) ÷150 = 8 (days)
A: It will take another eight days.
4、∠2= 180 -2∠2= 180 - 120 =60
Answer: ∠2 is 60 times.
Fourth, use your head.
192÷ 12= 16
2880÷ 12=240
16×240=3840
A: The product of two numbers is 3840.