I would solve this by calculating the percentage of dislikes that makes up to this amount of likes:
First one, "The True Science of Parallel Universes" would be:
5/300)*100 = 1.66
Second one, "did the Past Really Happen?" would be:
7/400)*100 = 1.75
The first one has less dislikes compared to likes. So "The True Science of Parallel Universes" is the video that is better liked
Yes because it cant be divided down anymore
(x , y) = (7, - 1)
2x + 3y = 11 → (1)
3x + 3y = 18 → (2)
subtracting (1) from (2) term by term eliminates the y- term
(3x - 2x) + (3y - 3y) = (18 - 11)
x + 0 = 7 ⇒ x = 7
substitute x = 7 into either of the 2 equations and solve for y
(1) → (2 × 7) + 3y = 11
14 + 3y = 11
subtract 14 from both sides
3y = 11 - 14 = - 3
divide both sides by 3
= - 1
solution is (7 , -1)