Rational multiplication and division of mixed operations, calculation problems (- 13 / 2) × 2 / 3-0.5 × 2 / 7 + 1 / 3 × (- 13 / 2) - 5 × 0.5 (- 1 / 42) divided by (1 / 6-2 / 7 + 2 / 3-3 / 14) It's two calculation problems

Rational multiplication and division of mixed operations, calculation problems (- 13 / 2) × 2 / 3-0.5 × 2 / 7 + 1 / 3 × (- 13 / 2) - 5 × 0.5 (- 1 / 42) divided by (1 / 6-2 / 7 + 2 / 3-3 / 14) It's two calculation problems

Question 1:
Original formula = (- 13 / 2) × 2 / 3-1 / 2 × 2 / 7 + 1 / 3 × (- 13 / 2) - 5 / 7 × 1 / 2
=(-13/2)×(2/3+1/3)-1/2×(2/7+5/7)
=(-13/2)×1-1/2×1
=-13/2-1/2
=-(13/2+1/2)
=-7
2 questions
Original formula = (- 1 / 42) / (1 / 6-2 / 7 + 2 / 3-3 / 14)
=(-1/42)÷[(1/6+2/3)-(2/7+3/14)]
=(-1/42)÷(5/6-1/2)
=(-1/42)÷1/3
=(-1/42)×3
=-1/14

On the mixed operation of multiplication and division of rational numbers in grade one
The four rational numbers 3,4, - 6,10, the use of addition, subtraction, multiplication and division, you can use brackets, each number can only be used once, so that the result is 24!

3*【（-6）+10+4】
10-【3*（-6）】-4
（10-4）-【3*（-6）】

Primary school has been the sixth grade multiplication and division of quantitative relations

Search on the Internet by yourself. There are many specific ones, but the general ones are as follows:
Speed time distance
Unit price quantity total price
Working efficiency, working hours and working problems
Total number of copies per copy
According to the above, you can write a lot of quantitative relationships that you know and will use
Of course, we can also write many multiplication and division quantitative relations according to the relations among multiplication, division, fraction and ratio