Forming equations using proportion by Boxed Rockets

Form Equations to Represent the Following

Question 1:

y is inversely proportional to x, when x = 3, y = 12

y = \frac{36}{x}

Question 2:

y is inversely proportional to x, when x = 11, y = 14

y = \frac{154}{x}

Question 3:

y is inversely proportional to x, when x = 9, y = 15

y = \frac{135}{x}

Question 4:

y is directly proportional to x, when x = 11, y = 110

y = 10 x