Find the fourth proportional of 3 hours 20 minutes, 1 hour 50 minutes, and 6 hours 20 minutes.
Show answer & explanation
Correct answer: B
Explanation
The Correct answer is option 2 i.e. 3 hours 29 minutes.
Given that
The fourth proportion of 3 hours 20 minutes, 1 hour 50 minutes, and 6 hours 20 minutes.
Let a, b, c, and d are in proportion
Fourth proportional d = bc/a
Given, a = 3 hours 20 minutes = 200 minutes
b = 1 hour 50 minutes = 110 minutes
c = 6 hours 20 minutes = 380 minutes
According to the question;
d = bc/a
d = (110 × 380)/200 = 41800/200 = 209 minutes = 3 hours 29 minutes