(1)156×7-624
=1092-624
=468;
(2)24×6+75×6+6
=(24+75+1)×6
=100×6
=600;
(3)99×64+64
=(99+1)×64
=100×64
=6400;
(4)123-68+32
=55+32
=87;
(5)287×5+96990÷318
=1435+305
=1740;
(6)44×25
=4×11×25
=4×25×11
=100×11
=1100;
(7)3200÷4÷25
=3200÷(4×25)
=3200÷100
=32.