Xiao Ming climbs the stairs twice as fast as Xiao Li. Xiao Li has climbed to the fourth floor, and Xiao Ming has climbed to several floors

Xiao Ming climbs the stairs twice as fast as Xiao Li. Xiao Li has climbed to the fourth floor, and Xiao Ming has climbed to several floors

(4-1) × 2 + 1 = 7th floor
A Xiaoming climbs to the 7th floor

Xiaodong and Xiaoli compete to climb the stairs. Xiaodong runs to the 5th floor, and Xiaoli just goes to the 4th floor. At this speed, when Xiaodong runs to the 21st floor, what floor does Xiaoli run to?

Xiaodong runs to the 5th floor and needs to climb the stairs of the 4th floor. Xiaoli runs to the 4th floor and needs to climb the stairs of the 3rd floor. The speed ratio between Xiaodong and Xiaoli is 4:3. When Xiaodong runs to the 21st floor, she needs to climb the stairs of the 20th floor. 20 × 3 / 4 = 15. When Xiaodong runs to the 21st floor, Xiaoli runs to the 15th floor. If my answer can help you, or click the upper right corner of the mobile client

As shown in the picture, Xiaofang looks at Xiaoli in the direction of 50 ° north by East, and Xiaoli looks at Xiaofang in the direction of 50 ° north by East______ In the right direction

50 ° by the east of the north is opposite to 50 ° by the west of the south. 50 ° by the west of the south is 40 ° by the south of the West. So Xiao Li sees that Xiao Fang is 40 ° by the south of the West or 50 ° by the west of the south