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Three out of seven minus two out of 21
3 / 7-2 / 21
=9 / 21-2 / 21
=7 out of 21
=1 / 3
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Calculate 0 - (- 5) - (+ 6) (+ 2,3 / 7) - (+ 4,3 / 14) - (- 2,3 / 14)
Is the subtraction of rational numbers
0-(-5)-(+6)
=5-6
=-1
(+ 2 3 / 7) - (+ 4 3 / 14) - (- 2 3 / 14)
=2 and 3 / 7 + (- 4 and 3 / 14 + 2 and 3 / 14)
=2 and 3 / 7-2
=3/7
(- 7 / 3) / (- 1 / 6) - 4 / 3 * (- 2 / 3)
emergency
(- 7 / 3) / (- 1 / 6) - 4 / 3 * (- 2 / 3)
=-7x of 3 (- 6 of 7)) - 4 of 3 * (- 10 of 3)
=2 + 40 / 9
=Two and 40 out of nine
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56:14 simplification is more important than process
56：14＝（4*14）：14＝4：1
The number of male students in class 6 (3) is 6 / 7 of that of female students. The number of male students is a little less than that of female students, and the number of female students is a little more than that of male students
Male + Female = 1;
Male = 6 / 7 female;
Let's say six men and seven women. The total number is 13
So men are 1 / 13 less than women, and women are 1 / 13 more than men
There were 40 students in a certain class, among which 3 / 4 were girls. Now how many boys are transferred? At this time, girls account for 1 / 2 of the class. How many boys are transferred?
First of all, calculate the number of girls in 40 people, 40 times 3 / 4, get 30 people, then there are 10 boys at this time;
The number of female students remains unchanged, but it has changed from 3 / 4 to 1 / 2. Divide 30 by 1 / 2 to get 60, which is the number of students in the whole class;
60 minus 30 girls, there are 30 boys at this time, minus the original 10 boys, there are 20 new boys
There were 42 students in class 1 of grade 6, of whom 4 / 7 were boys. Then there were some girls. At this time, the ratio of boys to girls was 6:5
There were 42 students in class 1 of grade 6, of which 4 / 7 were boys. Then there were several girls. At this time, the ratio of boys to girls was 6:5. How many are there now?
The total number of male students is 42 × (4 / 7) = 24
Female students: 42-24 = 18
Let x girls be transferred, then 24 / (18 + x) = 6 / 5, and the solution is x = 2
So now there are 42 + 2 = 44 people
There were 42 students in the first class of grade 4, of which 4 / 7 were boys. After several girls were transferred, the ratio of boys to girls was 6:5
How many students
42 * (4 / 7) = 24 / 6 * 5 = 20 42-24 = 18 20-18 + 42 = 44 hope to adopt!
There are 90 girls in Grade 6, 10% less than boys. How many students are there in Grade 5?
Male students: 90 (1-10%) = 100
Total students: 90 + 100 = 190
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There are 380 students in Grade 6. The number of girls is 90% of that of boys. How many boys and girls are there?
Formula!
380 (1 + 90%) = 200 (male)
380-200 = 180 (female)
Or 200 × 90% = 180 (female)
RELATED INFORMATIONS
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