Answer:
Down the left-hand column, the pattern is counting by 5's. Therefore, 5, 10, 15, 20, 25. Down the right-hand column, the pattern is counting by 4's. Therefore, 4, 8, 12, 16, 20. Thus, the ratios are:
5:4
10:8
15:12
20:16
25:20
In other words, the first line (5:4) is the base ratio. The second line multiplies the original values by 2, the third line by 3, the fourth line by 4, and the fifth line by 5.
1/√6 - √11 + √5
LCM = √6
(1 - (√6)*(√11) + (√5)*(√6) ) / √6
(1 - √(6*11) + √(5*6) )/ √6
Rationalize the surd by multiplying top and bottom by √6
((1 - √(6*11) + √(5*6) )/ √6) * (√6/√6)
(√6 - √(6*6*11) + √(5*6*6)) / √6
(√6 - 6√(11) + 6√(5)) / 6
So answer is:
(√6 - 6√11 + 6√5) / 6