In an examination, 70 students secured first class marks in English or Maths Out of these, 43 students obtained first class Marks in Maths and 9 in English and Maths both. How many students have secured first class marks in English only?
Imagen this as a venn diagram, if there are 9 first class math and english marks in the middle, and 70 first class only english marks + first class math and english marks, you have to take alway the number of first class math and english marks. So if you do that, you get 70-9=61.