1, the original formulas =3 and 9 4-2 and 17, 1 1+2 and 5-9.
=(3 and 4+2 and 5/9)-2 and 65438+ 1 1.
=6-2 and 17 parts 1 1
=3 65438+6/07
2. The original formula = (2/3+9× 9/28 )×165438+12/0.
= (2/3+ 1) × 165438+ 12/0.
= 12 point11×11point 12 point
= 1
3. The original formulas = 1 and 2/3× [7 and 5/6+ 14 and 5-3 and 1-4 and 1].
= 1 and 2/3× [7 and 5/6+ 1 and 2/6 1-4 and 1]
= 1 2/3 × [7 5/6 7 1]
= 1 and 2/3× 15
=25
4.0.4x= 1 plus 7 1×3 plus 2 1
0.4x=4
x= 10