To find this percentage, it will make it easier if it is worded differently. Put it "15 is what percent of 50?"
To find the percentage, simply divide 15 by 50 then multiply that quotient by 100.
15 / 50 = 0.3
0.3 x 100 = 30 = 30%
True is the answer for this question
3y - x = a
To solve for y we isolate the y variable.
3y = x + a
y = (x + a)/3
so let's firstly find the component form of "u", keeping in mind that "v" is really in the opposite direction and twice as long, so v = -2u.

Unit rate of 1st Can = 1.14/8 = $0.1425
Unit rate of 2nd Can = 1.75/12 = $0.145
1st Can is cheaper than 2nd one