Answer:

when
,
, and
,
Explanation:
If
varies jointly as
,
, and
, the equation of variation is given by:

where
is the constant of variation.
To find the constant
, substitute the given values
,
,
, and
into the equation:




Now that we have the constant of variation
, we can use it to find
when
,
, and
:



Therefore, when
,
, and
, the value of
is 54.