Suppose j varies jointly with g and v, and j=1 when g=6 and v=3.

Find the constant variation and find j when g=8 and v=11

Verified Answer :

"Joint variation" means "directly, but with two or more variables". Thus, we write as follows:

j 
α gv

We insert proportionality constant k, to change it to equality.

j = kgv

We solve k,

1 = k (4)(3)
k =1/12

j = gv/12
j = 8(11)/12
j = 22/3

Answer:

The constant of variation is \(\frac{1}{18}\)

Value of j is \(\frac{44}{9}\)

Step-by-step explanation:

Given,

j varies jointly with g and v,

That is,

j ∝ gv

⇒ j = k(gv)

Where, k is the constant of variation,

We have, j = 1 when g = 6 and v = 3

⇒ 1 = k(6 × 3) ⇒ 1 = 18k ⇒ k = \(\frac{1}{18}\)

Thus, the equation that shows the given relation in j, g and v is,

\(j=\frac{1}{18}(gv)\)

If g = 8, v = 11,

\(j=\frac{1}{18}\times 8\times 11=\frac{88}{18}\implies j=\frac{44}{9}\)