One-fourth of the cars that an automobile manufacturer produces are sports cars, and the rest are sedans. if one-fifth of the cars that the manufacturer produces are red and one-third of the sports cars are red, then what fraction of the sedans is red

Step-by-step explanation:

Let's base this on 100%, or 100 cars, which is 100% of the cars.  If 1/4 of the 100 cars are sports cars, then we have

25 sports cars and

75 sedans

If 1/5 of the total cars are red, 20 of the 100 cars are red (since 1/5 is 20).  

If 1/3 of the sports cars, of which we have 25, are red, then 25/3 of the sports cars are red.  

Since we have 20 total red cars and 25/3 of them are sports cars, then the rest of them must be red sedans:

Total red cars - red sports cars = red sedans

which simplifies to