Three, four, five and a can be used to form a proportion. The maximum of a is [], and the minimum of a is []

Three, four, five and a can be used to form a proportion. The maximum of a is [], and the minimum of a is []

Multiply the two largest numbers to get 20
20 △ 3 = 20 / 3 [maximum]
Multiply the least two numbers to get 12
12 △ 5 = twenty fifths [minimum]

Add a number to 4.5.6 to form a proportion. What are the three numbers

4：5=6：7.5
5：6=4：4.8
6：5=4：20/6

Add 0.1,1,3 / 5 and 0.2 to form a proportion. This number can be?

Question 0.11.60.2 with a number, the proportion, the number can be? There are three answers
0.1：1.6=1/16 0.2：X=1/16 X=3.2
0.6：0.1=16 0.2：X=16 X=1/80
0.1：0.2=1/2 1.6：X=1/2 X=3.2
0.2：0.1=2 1.6：X=2 X=0.8
1.6：0.2=8 0.1：X=8 X=1/80
0.2：1.6=1/8 0.1：X=1/8 X=0.8

Three classes donated money to hope primary school, (1) one third of the total donation to grade 7, (2) one third of the total donation to grade 7
(1) Half of the sum of the donations for class (3) and class (3) is known. Class (3) has donated 380 yuan. What is the total donation for Grade 7

Arithmetic method:
The number is "1"
(380 + 380 △ 2) △ 1-1 / 3-1 / 2 × 1 / 3) = 1140, which is the total amount,
1140 × 1 / 3 = 380 (1 shift)
(380 + 380) △ 2 = 380 (2 shifts)
Class 3 380

A, B and C three schools donated books to hope primary school in poor mountainous areas. It is known that they donated 2400 books in total, and three schools donated books
The ratio of a, B, C to donated books is 1; 3; 2. (1) how many books are donated by each of the three schools? (2) if the condition a, B, C = 1; 3; 2 is changed to a: B = 2:3, B; C = 3; 5, the condition remains unchanged, how many books are donated by each of the three schools?

The ratio of a, B and C is 1:3:2, which means that a accounts for 1 / 6, B accounts for 3 / 6, i.e. 1 / 2, C accounts for 2 / 6, i.e. 1 / 3. Therefore, among the three schools, the books donated by a are 2400 × 1 / 6 = 400; the books donated by B are 2400 × 1 / 2 = 1200; the books donated by C are 2400 × 1 / 3 = 800
(2) From a: B = 2:3, B: C = 3:5, then a: B: C = 2:3:5, as mentioned above, among the three schools
Books donated by Party A: 2400 × 1 / 5 = 480; books donated by Party B: 2400 × 3 / 10 = 720; books donated by Party C: 2400 × 1 / 2 = 1200

My class donates 6 yuan for each boy and 4 yuan for each girl. My class donates 5 yuan on average______ ．

Total amount of money △ total number of donations = average number of donations per person; if the number of boys and girls in the class is equal, this question is right; if the number of boys and girls is not equal, it is wrong; this question does not know how many boys and girls there are respectively, so it is wrong

The students actively contribute their love to the "Hope Project". Class one of six years donates 100 yuan. Class two of six years donates 4 yuan more than class one of six years. How much more?
After answering the questions,

4/100=4%

A total of 40 students from class 6 (2) of a school donated 100 yuan for "Hope Project". The donation situation is as follows
Donation (yuan)
Number of people 6 7
The number of people who donated 2 yuan and 3 yuan is not clear because of ink pollution. How many students each asked for 2 yuan and 3 yuan?

Donation 2 yuan x
Donation 3 yuan y
6+7+x+y=40
6+28+2x+3y=100
x=15
y=12
15 and 12 students donated 2 yuan and 3 yuan respectively

In the following formulas, the largest result is ()
A. 3457B. 34÷57C. 57÷34

34 ／ 57 ＞ 34 = 47.6, 57 ／ 34 ＜ 57, so 34 ／ 57 ＞ 3457 ＞ 57 ／ 34 is selected: B

30 tons in the first quarter, 38 tons in the second quarter and 34 tons in the third quarter
(1) How much less in the first quarter than in the second?
(2) If the fourth quarter is 20% more than the third quarter, how many tons are there in the fourth quarter?
(3) Can you ask other percentage questions and answer them

（1）：（38-30）/38
（2）：34*（1+20%）
(3) : what percentage of the second quarter in the first quarter? 38g30