In a certain examination, 72 candidates offered mathematics, 64 offered English and G2 French. 18 offered both mathematics and English, 24 mathematics and French, and 20 - English and French. 8 candidates offered all the three subjects. How many candidates were there?
Q. In a certain examination, 72 candidates offered mathematics, 64 offered English and G2 French. 18 offered both mathematics and English, 24 mathematics and French, and 20 - English and French. 8 candidates offered all the three subjects. How many candidates were there?
Identify Sets and Relationships: Identify the sets and their relationships.We have three subjects: Mathematics, English, and French. Some candidates offered multiple subjects. We need to use the principle of inclusion-exclusion to find the total number of candidates.
List Given Numbers: List the given numbers.Candidates who offered Mathematics: 72Candidates who offered English: 64Candidates who offered French: G2 (unknown)Candidates who offered both Mathematics and English: 18Candidates who offered both Mathematics and French: 24Candidates who offered both English and French: 20Candidates who offered all three subjects: 8
Apply Inclusion-Exclusion Principle: Apply the principle of inclusion-exclusion.Total candidates = Candidates in Mathematics + Candidates in English + Candidates in French - (Candidates in both Mathematics and English) - (Candidates in both Mathematics and French) - (Candidates in both English and French) + Candidates in all three subjects
Substitute Known Values: Substitute the known values into the equation.Total candidates = 72+64+G2−18−24−20+8
Simplify the Equation: Simplify the equation.Total candidates = 72+64−18−24−20+8+G2Total candidates = 136−62+G2Total candidates = 74+G2
Notice Missing Value: Notice that we do not have the value for G2, the number of candidates who offered French. Without this value, we cannot determine the exact total number of candidates.