Student: Find the third proportional to 4 and 16?\nOptions:\n(A) 80\n(B) 12\n(C) 64\n(D) 78\n(E) 72.
Another student: Let's say, hmmm...

User
Formula = Third proportional = (b × b)/a\nA = 4 and B = 16\n(16 × 16)/ 4 = 256/4 = 64 Final answer: (C).
Assistant