问题 解答题
下面各题怎样算简便就怎样算.
8470-104×65
168.1÷(4.3×2-0.4)3.64÷4+4.36×0.25
78×19950×32×125
1
9
-
1
12
)×4×9
99×99+991.3-3.79+9.7-6.212.4×[(3.6+1.4)÷
5
6
].
答案

(1)8470-104×65

=8470-6760

=1710;

(2)168.1÷(4.3×2-0.4)

=168.1÷(8.6-0.4)

=168.1÷8.2.

=20.5;

(3)3.64÷4+4.36×0.25

=0.91+1.09

=2;

(4)78×199

=78×(200-1)

=78×200-78×1

=15600-78

=15522;

(5)50×32×125

=50×(4×8)×125

=(50×4)×(8×125)

=200×1000

=200000;

(6)(

1
9
-
1
12
)×4×9

=

1
9
×4×9-
1
12
×4×9

=4-3

=1;

(7)99×99+99

=99×(99+1)

=99×100

=9900;

(8)1.3-3.79+9.7-6.21

=(1.3+9.7)-(3.79+6.21)

=11-10

=1;

(9)2.4×[(3.6+1.4)÷

5
6
]

=2.4×[5÷

5
6
]

=2.4×6

=14.4.

不定项选择
单项选择题