①15.3+6.72+5.7+23.28
②×+÷
③0.6×7.1+2.9×
④48×(﹣)
(1)630+270÷18×15 (2)
(3) (4)
(5) (6)
①1204+879+121
②74×60%+×25+0.6
③1.2÷×(0.6﹣)
④×[﹣(+)]