Algebraic Direct Proportion

A is directly proportional to B. When A is 30, B is 15.

Form an equation which relates A to B.

• A = 2B

• A = 0.5B

• B = 2A

• B = 0.5A

Y is directly proportional to X. When Y is 24, X is 8.

Find Y when X = 5

• $Y\ =\ \frac{8}{3}$
  

• Y = 24

• Y = 15

• Y = 8

F is directly proportional to T. When F is 36, T is 6.

Find F when T = 7

• F = 6

• F = 42

• F = 36

• $F\ =\ \frac{7}{6}$

Y is directly proportional to X. When Y is 8, X is 40.

Find Y when X = 20

• $Y\ =\ \frac{4}{5}$

• Y = 4

• Y = 5

• $Y\ =\ \frac{1}{5}$

A is directly proportional to B. When A is 3, B is 12.

Find A when B = 24

• A = 6

• A = 144

• $A\ =\ \frac{1}{4}$

• $A\ =\ 4$

Y is directly proportional to X. When Y is 5, X is 15.

Find Y when X = 7

• $Y\ =\ \frac{3}{7}$

• $Y\ =\ \frac{7}{5}$

• Y = 21

• $Y\ =\ \frac{7}{3}$

R is directly proportional to P. When R is 16, P is 64 .

Find P when R = 4

• P = 16

• P = 4

• $P\ =\ \frac{1}{4}$

• $P\ =\ \frac{1}{16}$

C is directly proportional to X. When C is 32, X is 4.

Find X when C = 104

• X = 832

• $X\ =\ \frac{1}{8}$

• X = 13

• $X\ =\ 3\frac{1}{4}$

Y is directly proportional to X. When Y is 30, X is 5.

Find Y when X = 12

• Y = 36

• $Y\ =\ \frac{1}{6}$

• Y = 2

• Y = 72

D is directly proportional to E. When D is 4, E is 40.

Find D when E = 348

• D = 4

• D = 87

• D = 3480

• D = 174