(1)30.9÷[14-(9.85+1.15)]
=30.9÷[14-11]
=30.9÷3
=10.3;
(2)1.2×7.26+1.2×2.74
=1.2×(7.26+2.74)
=1.2×10
=12;
(3)0.25×32×12.5
=(0.25×4)×(8×12.5)
=1×100
=100;
(4)21.14+9.2×1.3
=21.14+11.96
=33.1;
(5)7.8÷0.15÷4
=52÷4
=13;
(6)7.1×101
=7.1×(100+1)
=7.1×100+7.1
=710+7.1
=717.1.