Name _ _ _ _ _ _ _ Student ID _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

First, fill in the blanks. (***24 o'clock, 1 point/space)

1. There are 24 boys and 6 girls in the art group1. The ratio of the number of boys to the number of girls is (), and the ratio of the number of boys to the total number is ().

2.3.4 = 9: () = (): 24 = = () (fill in decimal places)

3. The former item of the ratio is 60, the ratio is 0, and the latter item is ().

Multiply the previous term of 4.5: 8 by 3. In order to keep the proportion unchanged, the latter item should be ().

The simplest integer ratio of 5. : 0.5 is () and the ratio is ().

6. The ratio of basketball to volleyball is 6: 7, basketball accounts for () of the total number of two kinds of balls, and volleyball accounts for () of the total number of two kinds of balls.

7. Dong Li put 5g of sugar into100g of water to make syrup. The ratio of sugar to water is (), and the ratio of sugar to syrup is ().

8. When Wang Ming read Grimm's fairy tales, the ratio of pages read to pages not read was 5: 8, and the number of pages read accounted for () of the whole book and () of the rest of the book was unread.

9.A number ÷ B number = 1, the ratio of B number to A number is (), and the ratio of A number to the sum of two numbers is ().

10. The radius of the big circle is 6 cm, the radius of the small circle is 4 cm, the diameter ratio of the big circle to the small circle is (), the perimeter ratio is (), and the area ratio of the small circle to the big circle is ().

The ratio of 1 1.A, b and c is 1: 2: 3, and their average value is 30, so the number b is ().

12. The orange juice stewed eggs steamed with 10g orange juice and 50g egg liquid are the best. Egg stew 1200mg orange juice requires 1g orange juice and 50g egg liquid.

Second, multiple choice questions. (*** 10 point)

50 students in class 1.6 (4). One day, three people were late and two people were ill. The ratio of absenteeism to the number of students in the class is ().

A. 1 :25 C. 3 :50

2. The ratio of the degrees of the three internal angles of a triangle is 5: 3: 2, and this triangle is ().

A. acute triangle B. right triangle C. obtuse triangle

The number of roosters is the number of hens. The following statement is correct ().

A. The ratio of rooster to hen is 5: 3.

B: The ratio of hens to the total number of cocks and hens is 5: 8.

C. the number of cocks is less than that of hens.

4. The area ratio of parallelogram to equilateral triangle is ().

1: 1 b . 1:2 c . 2: 1

5. If A is equal to B, the simplest integer ratio of A and B is ().

A.4 :5 B. 5 : 4 C:

Third, the calculation problem. (***34 points)

1. (10)

÷= 6×= += ×= 45×=

0÷= ÷= ÷ = ×= ÷=

2. Find the ratio. (12)

3.6:4.5 12 : 144 0.25 : :

3. Simplify the proportion. (12)

0.4: 2.8m: 36cm: 48: 1.6

Fourth, the operation questions. (***4 points)

/kloc-0 1.□□□□□□□□□ (color, so the ratio of the number of □ to the number of black is 1: 2. )

2. Divide the lower parallelogram into two parts so that their area ratio is 1: 3.

Fifth, solve the problem. (***28 points)

1.6 (1) Class donated money to Hope Primary School 1 120 yuan. The ratio of male to female donations is 3: 4. How much did each of them donate?

2. The ratio of the number of buses and cars parked in the parking lot is 5: 7, and there are 35 cars parked. How many buses and cars are parked in the parking lot?

3. Prepare a kind of milk, and the ratio of milk powder to water is 1: 30.

(1) How many kilograms of water does 500 grams of milk powder need?

(2) How many grams of milk powder should be added to 60 grams of water?

The circumference of rectangle is 48 cm, and the ratio of length to width is 7: 5. How many centimeters is the length and width of this rectangle? How many square centimeters is the area?

5. Three families 10 paid the water fee in 72 yuan, and distributed the water fee to households according to the population. There are three kings, four Zhang families and five Li families. How much water does each household have to pay?

6. Passenger cars and trucks leave from two places 405 kilometers apart at the same time and meet in 4.5 hours. As we all know, the speed ratio of buses and trucks is 5: 4. How many kilometers do buses and trucks travel per hour?

7. The construction site uses 1 part cement, 2 parts yellow sand and 3 parts stones to prepare a kind of concrete. Now we need to prepare 6 tons of concrete. Is it enough to use 10 bags of cement of the brand shown in the picture?

Sixth, thinking expansion. (***20 points)

1. Enclose a right triangle with 60 cm. The length ratio of the three sides of this triangle is 3: 4: 5. What is the height of the hypotenuse of this right triangle?

2. After several numerator and denominator are added at the same time, the ratio of numerator and denominator is exactly 1: 2?