The calculation problems of the seventh grade of mathematics (about positive numbers and negative numbers) can be simple and convenient.

Step 1: Change -2.75 and 2. 125 into scores of-2.75 =-412.125 = 817.

Step 2: You will find that some denominators are the same, so you put them in brackets.

The denominator is 4: 18 and 3/4 {did you know that 18 and 3/4 are actually equal to 75/4? The denominator of }+(-4 1 1) is 8: (8 17)+ (-4 and 8 1)+(-2 and 8 7)+ (- 1 and 8 1. 3 2/5)+(5 3/5) The denominator is12: (-3 65438+5/02)+(+5 65438+5/02) The denominator is 6: (+5 5 5/6)+(-6 1).

Step 3: Add the scores with the same denominator.

The denominator is 4: 75+(-11) = 64 =16.

The denominator is 8: 817+(-8 33)+(-8 23)+(-8 9) =-8 48 =-6.

The denominator is 7: 7 89+(-7 22)+(-711) =-7 44.

The denominator is 5: 5 17+5 28 = 5 45 = 9.

The denominator is12: (-65438+4/0)+( 12)+(65 of12) = 24 of12 = 2.

The denominator is 6: 6 35+(-6 37)= -6 2 = -3 1.

Step 4: Add up all the figures.

16+(-6)+(44 out of 7)+9+2+(65438 out of 3+0) = 21+(44 out of 7)+(65438 out of 3+0).

Step 5: Divide equally (make the denominator 2 1).

265438+44 1 {= 2 1}+(-265438+ 132)+(-265438+7) = 265438+302.

Which step is unclear? I don't understand. I'm asking ~