几道数学题,简便运算!!!

Question

1.(1又3/4 - 7/8 - 7/12) × (-1又1/7)

2.(-3)^2×＜(-2/3) + (-5/9)＞

3.(5/9 - 5/6 + 1/4) ÷ (-1/36)

4.(-19又18/19) × 38

注意:过程要详细!!!四题里都有负数```

Answer 1

解：1.原式=(7/4-7/8-7/12)×(-8/7)
=-8/7×7/4+8/7×7/8+8/7×7/12
=-2+1+2/3
=-1/3

2.原式=9×(-2/3)+9×(-5/9)
=-6-5
=-11

3.原式=(5/9 - 5/6 + 1/4) ×(-36)
=-36×5/9+36×5/6-36×1/4
=-20+30-9
=1

4.原式=(-20+1/19)×38
=-20×38+1/19×38
=-760+2
=-758

Answer 2

1.(1又3/4 - 7/8 - 7/12) × (-1又1/7)
=（7/4-7/8-7/12）*（-8/7）
=7（1/4-1/8-1/12）*（-8/7）
=8*（1/4-1/8-1/12）
=8*1/4-8*1/8-8*1/12
=2-1-2/3
=1/3

2.(-3)^2×＜(-2/3) + (-5/9)＞
=9*[-2/3-5/9]
=9*（-2/3）-9*5/9
=-6-5
=-11

3.(5/9 - 5/6 + 1/4) ÷ (-1/36)
=(5/9 - 5/6 + 1/4) *（-36）
=-36*5/9+36*5/6-36*1/4
=-20+30-9
=1

4.(-19又18/19) × 38
=（-20+1/19）*38
=-20*28+38*1/19
=-560+2
=-558本回答被提问者采纳

Answer 3

1.(1又3/4 - 7/8 - 7/12) × (-1又1/7)
=(7/4-7/8-7/12)×(-8/7)
=-(7/4×8/7-7/8×8/7-7/12×8/7)
=-(2-1-2/3)
=-1/3

2.(-3)^2×＜(-2/3) + (-5/9)＞
=-9×(2/3+5/9)
=-(9×2/3+9×5/9)
=-(6+5)
=-11

3.(5/9 - 5/6 + 1/4) ÷ (-1/36)
=(5/9 - 5/6 + 1/4)×(-36)
=-(5/9×36- 5/6×36+ 1/4×36)
=-(20-30+9)
=1

4.(-19又18/19) × 38
=-(20-1/19)× 38
=-(20× 38-1/19× 38)
=-(760-2)
=-758

Answer 4

参照链接。
很高兴为你解决问题！

参考资料：http://hiphotos.baidu.com/071400225/pic/item/d64037550738df73564e00f2.jpeg

Answer 5

=(7/4-7/8-7/12)*(-8/7)
=7/24*(-8/7)
=-1/3

=9*(-11/9)
=-11

=(-1/36)*(-36)
=1

=279/19*38
=558