Several math problems should be solved by equations before 9:30 Someone originally planned to ride from place a to place B at the speed of 12 kilometers per hour, so that he could arrive at the specified time. However, he delayed the original planned departure time by 20 minutes, so he had to go at the speed of 15 kilometers per hour. As a result, he arrived at place B 4 minutes earlier than the specified time, and calculated the distance between ab A 3-meter-long iron wire is divided into two sections, making a square and a rectangular frame. It is known that the ratio of the length and width of the rectangle is 2:1, and the length of the rectangle is 0.3m more than the side of the square. Calculate the side length of the square, the length and width of the rectangle, and their respective areas Xiaobin he Xiaoming runs every morning. Xiaobin runs 4 meters and Xiaoming runs 6 meters 1. If they run at both ends of the 100 meter track at the same time, they will meet in a few seconds 2. If Xiaoming stands at the starting point of the 100 meter track and Xiaobing stands 10 meters in front of him, he can catch up with Xiaobing in a few seconds

Several math problems should be solved by equations before 9:30 Someone originally planned to ride from place a to place B at the speed of 12 kilometers per hour, so that he could arrive at the specified time. However, he delayed the original planned departure time by 20 minutes, so he had to go at the speed of 15 kilometers per hour. As a result, he arrived at place B 4 minutes earlier than the specified time, and calculated the distance between ab A 3-meter-long iron wire is divided into two sections, making a square and a rectangular frame. It is known that the ratio of the length and width of the rectangle is 2:1, and the length of the rectangle is 0.3m more than the side of the square. Calculate the side length of the square, the length and width of the rectangle, and their respective areas Xiaobin he Xiaoming runs every morning. Xiaobin runs 4 meters and Xiaoming runs 6 meters 1. If they run at both ends of the 100 meter track at the same time, they will meet in a few seconds 2. If Xiaoming stands at the starting point of the 100 meter track and Xiaobing stands 10 meters in front of him, he can catch up with Xiaobing in a few seconds

1. Let the distance between AB and ab be x km
x/12=x/15+(20+4)/60
5x=4x+24
x=24
2. If the width of the rectangle is x meters, the length of the rectangle is 2x meters, and the side length of the square is (x-0.3) meters
(x+2x)*2+(x-0.3)*4=3
10x-1.2=3
x=0.42
The side length of the square is 0.42-0.3 = 0.12M
The length of the rectangle is 0.42m, and the width is 2 * 0.42 = 0.84M
The area of the square is 0.12 * 0.12 = 0.0144 square meters
The area of the rectangle is 0.42 * 0.84 = 0.3528 square meters
3.1) set X seconds to meet
4x+6x=100
x=10
2) Set X seconds to catch up
6x=4x+10
x=5