Question

In a competition, a school awarded medals in different categiories.40 medals in sport 25 medals in danceand 212 medals in music, if the total of 55 students got medals and only 6 students got medals in the three categories ,how many students get medals in exactly two of these categories?

Answer 1

210

Note: this answer might be incorrect because of the value of music (212). This doesn't make logical sense.

Explanation:

Hello,

This question can easily be solved through the use of a venn diagram.

Total number of students = 55

Number of medals in sport = 40 = A

Number of medals in dance = 25 = B

Number of medals in music = 212 = C

Number of students that got award in the three categories = (AnBnC) = 6

n(AuBuC) = 55

n(AnB) + n(BnC) + n(AnC) - 3n(AnBnC) =

n(AnB) + n(AnB) + n(AnC) -3×6 ......equation (i)

n(AuBuC) = n(A) + n(B) + n(C) - n(AnB) - n(BnC) - n(AnC) + n(AnBnC)

Therefore,

n(AnB) + n(BnC) + n(AnC) = n(A) + n(B) + n(C) + n(AnBnC) - n(AuBuC)

n(A) + n(B) + n(C) + n(AnBnC) - n(AuBuC) - 18

40 + 25 + 212 + 6 - 55 - 18 = 210

Note: this answer might be incorrect because of the value of C (music)