Hey there!
2/3 = a/30
First: you have to CROSS MULTIPLY the given numbers
2(30) = 3(a)
2(30) = 60
3(a) = 3a
New EQUATION: 3a = 60
Second: DIVIDE 3 to BOTH SIDES
3a/3 = 60/3
CANCEL out: 3/3 because that gives you 1
KEEP: 60/3 because that helps you solve for your a-value
60/3 = a
60/3 = 20
Therefore, your answer is: a = 20
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)