Teacher:In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
Teacher: Now, understand the problem? Solve this instance: Problem: a solution of 90 litres contains milk and water in the ratio 7 : x . if 10 litres of water is added to the solution , the ratio becomes 3 : 2 , find the value of x ?
Options: a ) 2 , b ) 1.5 , c ) 3.5 , d ) 2.5 , e ) 3
Student:
c