Three professors were discussing over how long they have been teaching. Andrew and Beyonce have been teaching for a total of thirty six years. Curt and Beyonce have been teaching for a total of twenty two years. Curt and Andrew have been teaching for a total of twenty eight years.
Can you find out how long have each of them been teaching?
Answer
Andrew have been teaching for 21 years. Beyonce have been teaching for 15 years. Curt have been teaching for 7 years.
Let Andrew = A, Beyonce = B and Curt = C, then:
- A + B = 36
- B + C = 22
- A + C = 28
From equation (2), we get: B = 22 – C
From equation (3), we get: A = 28 – C
Substitute A and B into equation (1): (28 – C) + (22 – C) = 36
Solving for C gives 7. Substitute (C = 7) into equation(2) and (3)