解:0。3X=2。34 3X=234 X=78
0.3X=2.343X=234X=78
X-0.7X=2.341X-0.7X=2.340.3X=2.34X=2.34/0.3X=7.8
x-0.7x=2.34解;(1-0.7)X=2.34 X=2.34÷0.3 x=7.8
100x-70x=234 30x=234 x=7.8
0.3x=2.34 解:3x=234 x=78