In a donation drive, the ratio of notebooks to pens is 4:5. If there are 40 notebooks, how many pens are there?

On a playground, the ratio of swings to slides is 4:1. If there are 16 swings, how many slides are there?

The ratio of red jerseys to blue jerseys on a sports team is 2:3. If there are 36 blue jerseys, how many red jerseys are there?

In a parking lot, the ratio of cars to motorcycles is 5:2. If there are 50 cars, how many motorcycles are there?

At a fruit market, the ratio of apples to oranges is 6:7. If there are 42 apples, how many oranges are there?

At a concert, the ratio of adults to children is 3:2. If there are 90 adults, how many children are there?

In a recipe, the ratio of sugar to flour is 3:7. If the recipe uses 21 cups of flour, how many cups of sugar are needed?

The ratio of male swimmers to female swimmers in a team is 7:5. If there are 35 male swimmers, how many female swimmers are there?

On a farm, the ratio of chickens to ducks is 9:4. If there are 36 chickens, how many ducks are there?

In a classroom, the ratio of fiction books to non-fiction books is 7:4. If there are 28 fiction books, how many non-fiction books are there?

In a soccer club, the ratio of players who play forward to defenders is 2:3. If there are 14 defenders, how many forwards are there?

On a train, the ratio of passengers in first class to economy class is 2:9. If there are 18 first-class passengers, how many economy-class passengers are there?