解题思路:(1)按运算顺序从左往右依次运算;(2)运用乘法分配律简算;(3)先算括号内的乘法,再算括号内的加法,最后算括号外的除法;(4)先算除法,再算加法;(5)把原式变为0.74+9×0.74,运用乘法分配律简算;(6)运用除法的性质简算.
(1)91÷2.6÷0.05,
=35÷0.05,
=700;
(2)6.3×3.7+6.3×6.3,
=6.3×(3.7+6.3),
=6.3×10,
=63;
(3)(3.7+1.7×0.4)÷2.5,
=(3.7+0.68)÷2.5,
=4.38÷2.5,
=1.752;
(4)7.28+3.2÷2.5,
=7.28+1.28,
=8.56;
(5)0.74+0.9×7.4,
=(1+9)×0.74,
=10×0.74,
=7.4;
(6)7.8÷0.125÷0.8,
=7.8÷(0.125×0.8),
=7.8÷0.1,
=78.
点评:
本题考点: 小数四则混合运算;运算定律与简便运算.
考点点评: 此题考查了小数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律进行简便计算.