Hey there!
75% of ? = 30
75% of x = 30
75/100 * x = 30
75 ÷ 25 / 100 ÷ 25 * x = 30
3/4 * x = 30
MULTIPLY 4/3 to BOTH SIDES
4/3 * 3/4x = 4/3 * 30
CANCEL out: 4/3 * 3/4 because that gives you 1
KEEP: 4/3 * 30 because it helps solve for your answer
x = 4/3 * 30
SIMPLIFY IT
x = 40
Therefore, 75% of [40] = 30
Answer: 40
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)