(1) 12x10÷15+[(12+10)x4x2-2x2x2-1.5x1.5]÷10
=8+16.575
=24.575
需要25桶
(2)设大车a辆,小车b辆
20a+8b=128→b=16-2.5a
y=200a+120b=200a+120x(16-2.5a)=1920-100a
a越大,运费越少.128÷20=6余8 8÷8=1
应租用大车6辆,小车1辆
(1) 12x10÷15+[(12+10)x4x2-2x2x2-1.5x1.5]÷10
=8+16.575
=24.575
需要25桶
(2)设大车a辆,小车b辆
20a+8b=128→b=16-2.5a
y=200a+120b=200a+120x(16-2.5a)=1920-100a
a越大,运费越少.128÷20=6余8 8÷8=1
应租用大车6辆,小车1辆