Difficult Mixture Replacement Strategy To Find the Quantity Removed

NEXT:
The ratio of milk and water in mixture of 90 L is 7:2. If some amount of mixture is replaced by water, then ratio of milk to water becomes 5:2. Find the quantity of water added.

Anil kumar,fastest tricks,strategies,logical thinking,globalmathinstitute,global math institute,mathematics,gcse,igcse,cbse 10,sat,mcat,linear systems,grade 10 math,algebra 2,advance mathematics,solve equations,word problems,wordproblems,real life applications,grade 8,SSC,CGL,PO Bank,mixture replacement,mixture removal,mixture and allegation,