First, think carefully and fill in. (2 points for each question, 3 points for the fourth question, *** 19 points)

1. Divide a 3-meter-long iron wire into 5 segments on average, each segment is () meters long, and each segment accounts for () of the total length.

2. Walking from school to the cinema, A took 8 minutes, B took 9 minutes, and the time ratio between A and B was ().

3.0.6 and () are reciprocal.

4.()÷ 16 = 15: () = () (expressed in decimal)

5. When 1 × = 2, the score is ().

6.4: 10 The simplest integer ratio is (). If the former term of this ratio is multiplied by 5, the latter term should be () to keep the ratio unchanged.

7. The side length of a big square is three times that of a small square, so the area ratio of the big square and the small square is ().

8. The number of boys is equal to the number of girls, and the number of () is regarded as the unit "1".

9. The lengths of the three sides of a triangle are 15 decimeter, 18 decimeter and 2 1 decimeter respectively, and the length ratio of the three sides is ().

Second, can you become a master of judgment? (65438+ 0 for each question, ***7 points)

1.30: 10 The simplest integer ratio is 3. ( )

2. 1 kg equals 5 kg. ( )

3. Because the reciprocal of 1 is 1, the reciprocal of 0 should also be 0. ( )

4. The denominator of the latter item of ratio and fraction cannot be 0. ( )

5. Two ropes with the same length, the first one is used, the second one is used to remove rice, and the rest are equal in length. ( )

6. Class A has more people than Class B, and Class B has fewer people than Class A ... ()

7. When a number is divided by the true fraction, the quotient is not necessarily greater than this number. ( )

Third, be careful. (***9 points)

x\\\× 15×

Four, solve the equation, (**8 points)

1 1x- = X =

5. Find the ratio and simplify the ratio. (*** 12)

0.25:0.75 7.85: 1.25

: :

Sixth, solve the problems in life. (***45 points)

1. Xiao Min weighs 30 kilograms, which is the weight of his brother. His brother's weight is his father's. What's his father's weight? (7 points)

There are 360 peach trees in the orchard. Peach trees are pear trees, and apple trees are pear trees. How many apple trees are there? (7 points)

The school should plant 560 trees and distribute them to the fourth, fifth and sixth grades according to the ratio of 4:5:7. How many trees should be planted in each of the three grades? (8 points)

4. A car travels 45 kilometers per hour, and it takes 2 hours to travel from A to B, just reaching the midpoint of the two places. How many kilometers is it between A and B? (7 points)

The circumference of a rectangle is 20cm, and the ratio of length to width is 3:2. How many square centimeters is the area of this rectangle?

6. The ratio of students in grade five to grade six is 5:7. It is understood that there are 86 more students in grade six than in grade five. How many students are there in Grade Two? (8 points)