Think of the proportion of people as an actual number.
Namely: 3 men and 2 women.
In fact, the proportion of people is also simplified from the actual number of people.
Average score: (86×3+89×2)÷(2+3)
2. Party A, Party B and Party C * * 185 yuan. The ratio of money between Party A and Party B is 3: 4, and Party A is less than Party C by 5 yuan. How much does Party A have?
A is less than C. 5 yuan, A, B and C have 185 yuan.
If you subtract 5 yuan from C, A and C are the same.
Namely: A: B: C =3:4:3.
Of course, 5 yuan has to be subtracted from the total.
That is to say, Party A, Party B and Party C have 180 yuan, and the ratio of money among Party A, Party B and Party C is 3:4:3.
Find a 180 ÷ (3+4+3) × 3.
B 180 ÷ (3+4+3) × 4
C 180 ÷ (3+4+3) × 3+5
3. The sum of the reciprocal of two natural numbers is 7/ 12. These two natural numbers are () and ().
The reciprocal of a natural number is a true fraction in the form of1/x.
Then 1/X+ 1/Y=X+Y/XY.
That is, the denominator is the product of two natural numbers and the numerator is the sum of two natural numbers.
Only 1/3 1/4.
Answer 3 4
The circumference of an isosceles triangle is 45 cm, and the length of one side accounts for 2/9 of the circumference. How long are the three sides of this triangle?
The length of one side accounts for 2/9 of the circumference.
But this side may be the waist
There are 2/9: 2/9: 5/9
But 2/9+2/9 ≯ 5/9
That is, the sum of the two sides is not as much as the third side.
inconformity
Is it 2/9? :?
? =7/9÷2=7/ 18
The trilateral ratio is 2/9 :7/ 18:7/ 18.
That is 4 :7: 7.
Waist circumference 45 \u( 4+7+7)×7
Cardinality 45 ÷ (4+7+7) × 5
5. Three piles of coal A, B and C weigh 960 tons, two piles of coal A and B account for 5/8 of the total, and two piles of coal A and C account for 9/ 16 of the total. How many tons of coal are there in pile A?
Piles A and B account for 5/8 of the total, while piles A and C account for 9/ 16 of the total.
The sum of 5/8+9/ 16 is also a+b+a+C.
(5/8+9/ 16)- 1 to get one.
960×(5/8+9/ 16)- 1
Six, two bookshelves, the ratio of the number of books lent by Bookshelf A to the rest is 1: 3, and the ratio of the number of books lent by Bookshelf B to the rest is 2: 3. As we all know, two bookshelves borrow as many books. What is the ratio of books stored in two bookshelves?
The ratio of the number of books lent by a bookshelf to the rest is 1: 3.
The ratio of the number of books borrowed from the second shelf to the rest is 2: 3.
These two ratios are the ratio of the lent amount to the remaining amount.
Change and unification
The ratio of the number of books lent by a bookshelf to the rest is 1: 3.
That is 1: 3 = 2: 6.
The ratio of the number of books borrowed from the second shelf to the rest is 2: 3.
In this way, the number of books lent by bookshelves A and B is two.
It turns out that the ratio of books stored in two bookshelves is (2+6): (2+3).
Uncle Wang is going to form a rectangular chicken farm with walls and fences. It is known that the fence is 56 meters long and the length-width ratio of rectangular chicken farm is 3: 2. What is the largest area of this chicken farm?
The aspect ratio is 3: 2. As we all know, the maximum area of a wall can only be long.
The fence is 56 meters long, minute by minute, wide and wide.
And length: width: width =3:2:2.
Length 56(3+2+2)×3
Width 56(3+2+2)×2
The calculation part does the calculation by itself.