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Application problems of fractional math problems in junior high school
1. Riding a bike is 8 kilometers faster than walking, and the car is 24 kilometers faster than walking. Someone starts from place A, walks 4 kilometers first, then takes bus 10 km to place B, then takes bus 10 km to place B, and returns to place A by bike. Given the same round-trip time, find the walking speed of this person.

Assuming the walking speed is X, the cycling speed is 8+X and the car speed is 24+X.

4/x+ 10/(24+x)= 14/(8+x)

solve

X=6

A: The walking speed is 6 kilometers per hour.

2. Party A and Party B can complete a project in 36 days, with 45 days for Party A and 60 days for Party B and Party C. How many days does it take each person to complete it alone?

Set a to sit alone for x days and complete b, y, c and z days.

1/X+ 1/Y= 1/36

1/Y+ 1/Z= 1/60

1/X+ 1/Z= 1/45

solve

X=60

Y=90

Z= 180

Answer: It takes 60 90 180 days for one person to do it.

3. Given the radical positive number of x+a=- 1 in x-2, what is the value range of A?

(x+a)/(x-2)=- 1

x+a=2-x

2x=2 amps

x = 1-a/2 & gt; 0

a/2 & lt; 1

a & lt2