Question

Please help me answer this!

Answer 1

option B

`\frac{280}{√(L)\sqrt[3]{P}}`

Explanation:

Step 1

S varies inversely of the cube root of P

s
`\alpha`
`\frac{1}{\sqrt[3]{P} }`

s =
`\frac{k}{\sqrt[3]{P} }`

Step 2

S varies inversely with square root of L

s
`\alpha(1)/(√(L) )`

s =
`(k)/(√(L) )`

Step 3

Jointly

s =
`\frac{k}{√(L) \sqrt[3]{P} }`

Step 4

Plug values given in the question to find constant of proportionality

7 =
`\frac{k}{√(100)\sqrt[3]{64}}`

7 = k /(10)(4)

7 = k/40

k = 280

Step 5

General formula will be

s =
`\frac{280}{√(L)\sqrt[3]{P}}`