If n(P) = 20 and n(Q) = 30 and n(PuQ) = 40, find the value n(PnQ)
A
10
B
30
C
15
D
40
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
n(PuQ) = n(p) + n(q) - n(PnQ)
40 = 20 + 30 - n(PnQ)
n(PnQ) = 50 - 40 = 10
Source: WAEC / JAMB / NECO Classroom Archive (Record #64402)