A work can be finished in a day by 20 men, or by 30 women, or by 50 boys. 2 men and 5 boys work on alternate days and 6 women work on all days. If men work on the first day, the work is finished in ____ days.
4 \( \frac{1}{3} \)
3 \( \frac{1}{4} \)
4 \( \frac{1}{4} \)
3 \( \frac{1}{3} \)
Find the third proportional of (3 + \(\sqrt{2}\)) and 2 \(\sqrt{7}\).
2(3 + \(\sqrt{2}\))
(12 − \(\sqrt{8}\))
4(3 − \(\sqrt{2}\))
(12 + \(\sqrt{8}\))