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2. In a class of 52 students, 13 excel in Science and Mathematics, 16 excel in Science and Arts, 12 excel in Mathematics and Arts, 24 excel in Arts and 2 excel in none. Twice as many students excel in science only as do in mathematics only. The number of students who excel in mathematics only is six times the number of students who excel in Arts only. Determine the number of students who excelled in: (a) All the three subjects (b) Two subjects

User Livingtech
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a) Students excelling in all three subjects = 93 - 3x/2

b) Students excelling in two subjects = S ∩ M + S ∩ A + M ∩ A - 2 (subtracting the students excelling in all three subjects)

Let's break down the information given:

Let S = Students excelling in Science

Let M = Students excelling in Mathematics

Let A = Students excelling in Arts

Given:

Total students = 52

S ∩ M = 13 (Science and Mathematics)

S ∩ A = 16 (Science and Arts)

M ∩ A = 12 (Mathematics and Arts)

Students excelling in none = 2

Students excelling in Science only = 2x (Twice as many as Mathematics only)

Students excelling in Mathematics only = x

Students excelling in Arts only = x/6 (1/6th of Mathematics only)

Total students excelling in at least one subject = Total students - Students excelling in none

Using the principle of inclusion-exclusion, the formula for finding the total number of students excelling in at least one subject is:

Total = S + M + A - (S ∩ M) - (S ∩ A) - (M ∩ A) + (S ∩ M ∩ A)

From the given information, let's calculate the number of students excelling in at least one subject:

Total = S + M + A - 13 - 16 - 12 + (students excelling in all three subjects)

52 = S + M + A - 41 + (students excelling in all three subjects)

Students excelling in all three subjects = 52 - (S + M + A) + 41

Now, let's express S, M, and A in terms of x to solve:

S = 2x (Students excelling in Science only)

M = x (Students excelling in Mathematics only)

A = x/6 (Students excelling in Arts only)

Total = 2x + x + x/6 - 13 - 16 - 12 + (students excelling in all three subjects)

52 = 9x/6 - 41 + (students excelling in all three subjects)

52 = 3x/2 - 41 + (students excelling in all three subjects)

3x/2 + (students excelling in all three subjects) = 52 + 41

3x/2 + (students excelling in all three subjects) = 93

Now, solve for students excelling in all three subjects:

(students excelling in all three subjects) = 93 - 3x/2

Substitute this into the equation for the total number of students excelling in at least one subject:

52 = 3x/2 - 41 + 93 - 3x/2

52 = 52

This equation checks out and shows that the values for S, M, and A are consistent. So, the solution is:

a) Students excelling in all three subjects = 93 - 3x/2

b) Students excelling in two subjects = S ∩ M + S ∩ A + M ∩ A - 2 (subtracting the students excelling in all three subjects)

User Vahid Tajari
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