Question

F

is inversely proportional to
√
g
.
When
f
=
18
,
g
=
9

Work out
f
when
g
=
36

Answer 1

f = 9

Explanation:

f = k/square root of g (k is the constant) so 18 = k/square root of 9.

We can rearrange this to find k, so 18*square root of 9 = k

Consequently, k = 54

We can put k in our equation to now find f. f = 54/square root of 36

Therefore, f is 9

Answer 2

`\qquad \qquad \textit{inverse proportional variation} \\\\ \textit{\underline{y} varies inversely with \underline{x}} ~\hspace{6em} \stackrel{\textit{constant of variation}}{y=\cfrac{\stackrel{\downarrow }{k}}{x}~\hfill } \\\\ \textit{\underline{x} varies inversely with }\underline{z^5} ~\hspace{5.5em} \stackrel{\textit{constant of variation}}{x=\cfrac{\stackrel{\downarrow }{k}}{z^5}~\hfill } \\\\[-0.35em] \rule{34em}{0.25pt}`

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