In an examination, 40% of students passed in Maths only, 30% passed in Science only and 10% students failed in both subjects. If 200 students passed in science, find the total number of students by drawing Venn-diagram.​

Respuesta :

Answer:

  • 400 students

Step-by-step explanation:

Given:

  • 40% of students passed in Maths only
  • 30% passed in Science only
  • 10% students failed in both subjects
  • 200 students passed in science

Let the total number of students is x.

Then the number of students passed in both subjects is:

  • x - (0.4x + 0.3x + 0.1x) =
  • x - 0.8x =
  • 0.2x

Number of students passed in science is:

  • 0.3x + 0.2x = 200
  • 0.5x = 200
  • x = 200/0.5
  • x = 400

Venn diagram looks like below.

Consider 'Math' and 'Science' as two circles, 'Both' is the intersection of circles, 'Neither' is outside of the two circles.

  • Math         Both          Science            Neither
  • 40%          20%             30%                  10%