(1) Find the number of trees: There is an 800-meter-long expressway. On one side of the expressway, how many poplar saplings do you need to plant one poplar every 20 meters from beginning to end?

Exercise: 1 Set up telephone poles on one side of a 500-meter-long highway, and set up one every 50 meters. If both ends of the expressway are not erected, how many wires are needed?

On both sides of the 2.50-meter-long runway, a colorful flag is inserted every 5 meters from beginning to end. A * * *, how many colorful flags?

(2) Seeking the distance: A boulevard in the Red Scarf Park is 800 meters long, and 465,438+0 trash cans are placed at the same distance from beginning to end. What is the distance between every two trash cans?

Exercise: 1 On one side of a shady road, 86 poles were used from beginning to end. This tree-lined road is 1700 meters long. How many meters are there between every two telephone poles?

2. A tunnel in downtown park is 200 meters long, and cannas are planted on both sides of the tunnel from beginning to end at equal intervals, with a total of 82 cannas planted. How many meters are there between every two cannas?

(3) Seeking full length: A begonia tree was originally planted at one end of a straight road in the street park. Now one begonia tree is planted every 12 meter, and 25 saplings are used. How long is this road?

Exercise: 1 On both sides of an expressway, a telephone pole is set every16m, and 52 telephone poles are used. How long is this road?

There is a locust tree every 7 meters on both sides of the road. Fangfang took the tram for 3 minutes and saw a pagoda tree on the roadside. 15 1. What is the speed of the tram per minute?

(4) How many saplings do you need to plant a willow every 5 meters in a closed circular pond with a circumference of 300 meters?

Exercise: Plant 40 poplars every 2 meters around the circular pool. What is the circumference of the swimming pool?

A round fish pond is 200 meters long. Now 25 poplars are planted around the pond. How many meters can I plant?

(5), sawing wood

Example 1. There is a piece of wood, and I intend to cut each piece into three sections. It takes five minutes to cut every place. How many minutes does it take to finish sawing?

Practice, 1. There are three pieces of wood, and it takes 3 minutes to saw each piece of wood into 4 pieces. How many minutes does it take to read them all?

2. A carpenter saws a piece of wood with a length of 19 meters. He sawed a broken part 1 m first, then sawed it eight times and sawed it into many short pieces of wood with the same length. How long is each short piece of wood?

It takes 6 minutes for a piece of wood to be sawed into 4 sections, and the same piece of wood is sawed at the same speed. /kloc-How many knots can you saw in 0/8 minutes?

(6) Climbing stairs and ringing bells

Example 1: It takes 18 seconds for salesman Xiao Li to climb the first floor. How many seconds does it take him to climb the fourth floor?

Practice, 1. Xiao Li, a salesman, wants to contact the sixth floor. It took him 54 seconds to get from the sixth floor to the fourth floor. According to this calculation, how many seconds does it take for Xiao Li to walk to the sixth floor?

2. The wall clock strikes 6 times at 6 o'clock, and it strikes 10 second. Then knock 9 times at 9 o'clock, knock for a few seconds?

Feedback exercise:

1. Arbor Day is coming. Students plant trees on one side of a path with a length of 120 meters, and plant one every 6 meters.

(1) How many trees does * * * need if there are two kinds of trees at both ends?

(2) How many trees do you need if you only plant one?

(3) How many trees do you need if you don't plant trees at both ends?

2. A circular flower stand with a circumference of 80 meters, with a pot of orchids every 4 meters and a pot of roses every two pots. Q: * * How many potted flowers do you need?

3. On the anniversary of a factory, colored flags were inserted on both sides of the gate, with a distance of 3 meters between every two colored flags, and 62 colored flags were inserted from beginning to end. How long is this road?

The tree planting team plans to plant a row of trees on both sides of a road with a length of 100 meters. There are 52 trees at both ends of the road. How many meters is the average interval between every two adjacent trees?

5. A rectangular pond is100m long and 40m wide. How many trees need to be planted every 2 meters by the pond?

6. Xiao Gang forms a hollow square with pieces at equal distances, with 16 pieces on each side and one piece at each of the four vertices of the square. How many pieces did Xiao Gang use?

7. The wall clock strikes 5 times at 5 o'clock, and 10 seconds ends. Then, when 12 strikes 12, how many seconds does it end?

It takes six minutes to cut a piece of wood into three sections. If each section is equal in time, how many minutes does it take to cut seven sections?

9. There is a building with a height of 17 floors, and there are 17 steps between two adjacent floors. How many steps does it take for a person to climb from 1 to1?

10.AB raced to climb the stairs. When A ran to the third floor, B happened to run to the second floor. According to this calculation, when A ran to the ninth floor, which floor did B run to?