P varies jointly as m and u, and varies inversely as q. Given that p…

P varies jointly as m and u, and varies inversely as q. Given that p = 4, m = 3 and u = 2 and q = 1, find the value of p when m = 6, u = 4 and q =(frac{8}{5})

Correct Answer: Option C

Explanation

P (propto) mu, p (propto frac{1}{q})
p = muk ……………. (1)
p = (frac{1}{q}k)…. (2)
Combining (1) and (2), we get
P = (frac{mu}{q}k)
4 = (frac{m times u}{1}k)
giving k = (frac{4}{6} = frac{2}{3})
So, P = (frac{mu}{q} times frac{2}{3} = frac{2mu}{3q})
Hence, P = (frac{2 times 6 times 4}{3 times frac{8}{5}})
P = (frac{2 times 6 times 4 times 5}{3 times 8})
p = 10

There is an explanation video available below.