Answer:
20 :)
Step-by-step explanation:
The median of the set data set is 4
For 
between 
and 
, we have
is continuous over its domain, so the intermediate value theorem tells us that
is true for 
.
For all , we take into account that is 
-periodic, so the above inequality can be expanded to
where 
is any integer. Equivalently,
To get the corresponding solution set for
simply replace with 
:
Step-by-step explanation:
-3 (4a-5b)
=-3×4a -(-3×5b)
=-12a+15b
when
;
for
; and
for