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Pineapple Juice

Age 14 to 16 Short Challenge Level:

The Juice Drink company decides to mix leftover juice drinks to make a new drink.

They have 450 litres of pineapple drink, which is 42% juice.

They mix it with 630 litres of orange drink.

The new drink is 35% juice.

What percentage of the orange drink was juice?

This problem is taken from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.