4. 1.5 (/)4 additive commutative law
4.27/24,26/1Multiplicative Distribution Law
1.25 8 Multiplicative Exchange and Multiplicative Combination
②( 1000+ 100+ 10+ 1)-(0. 1*(×)4)
1 1 1 1-0.4
1 1 10.6
497-29 1+37
206+37
243
6。 92-( 1 1/8+ 1 1/3)+3。 18
6.92+3. 18- 1
10. 1- 1
9. 1
9/ 1*36+6/5*36_ 18/ 17*36
4+30- 14
20
9/4*[0/75+0.25- 16/7]
9/4*[ 1- 16/7]
9/4* 16/9
4/ 1
1.32*8/5+2.68*8/5
( 1.32+2.68)*8/5
````
3 \1.75kg = 2750g
0.05 kg = 50 g
500+50 = 550g
2750/550=5 times
5* 198=990 yuan
4. 12.9-2.3*3=6 yuan
6/(2+3)= 1.2 yuan
1.2+2。 3=3.5 yuan.