Question

if Q is directly proportional to P and if Q =28 when P =4,find law connecting P and Q, the value of Q when P=5, the value of P when Q =42

Answer 1

Given
Q is directly proportional to P
Therefore Q/P= constant
i) P=5, Q=?
28/4=Q/5
(28*5)/4=Q
35=Q
if P=5, Q=35
ii)P=?, Q=42
28/4=42/P
P=(42*4)/28
P=6

Answer 2

Answer:

(a) q=7p

(b) q=35

(c) p=6

Step-by-step explanation:

(a) law connecting P an Q, means an equation connecting Q an P

So,   q=kp    

After substituting,   28=k4

k=28/4           k=7

q=kp       So,   q=7p

(b)  As we know,   q=7p

So, after substituting the value, p=5

We Get,

q=7(5)           q=35

(c) As we know q=7p           So, p=q/7

So, after substituting the value, q=42

We Get,

p=42/7         p=6