Question

0.2x+1.2×3=8

Answer 1

解：解方程，此方程的解为x = 22

0.2x + 1.2 × 3 = 8

（2/10）x + （1×10+2）/10 × 3 = 8
（1/5）x + 12/10 × 3 = 8
（1/5）x + 6/5 × 3 = 8
（1/5）x + 18/5 = 8
（1/5）x = 8 - 18/5
（1/5）x = 40/5 - 18/5
（1/5）x = 22/5
x = 22/5 ÷ 1/5
x = 22/5 × 5
∴x = 22
答：此方程的解为x = 22

Answer 2

把能算的先额算出来，再利用加法算式的各部分之间的关系来解。
解：0.2x+1.2×3=8
0.2x+3.6=8
0.2x=8-3.6
0.2x=4.4
x=4.4÷0.2
x=22

Answer 3

0.2x+1.2×3=8
解：0.2x=8-1.2×3
0.2x=8-3.6
0.2x=4.4
x=4.4/0.2
x=22

Answer 4

0.2x+1.2×3=8
0.2x+3.6-3.6=8-3.6
0.2x÷0.2=4.4÷0.2
x=22

Answer 5

0.2x+1.2×3＝8
两边同乘以5，得
x+18＝40
x＝22