×减20%等于40
x=40+0.2
x=40.2
17减150%×等于6.5
1.5x=17-6.5
1.5x=10.5
x=7 ×减20%等于40
x=40+0.2
x=40.2
17减150%×等于6.5
1.5x=17-6.5
1.5x=10.5
x=7