Question 1073925
Calculating volumes is <b>not</b> necessary.  The same peanut butter would have the same density, no matter the net contents in a jar.  The "weight" or masses are given and those alone should be enough information.


If as given the price is based only on volume  ( or on mass ), then 
{{{18/2.89=22/x}}}


{{{18x=2.89*22}}}


{{{x=(2.89*22)/18}}}


{{{x=3.53}}}
The 22 ounce jar is  $3.53.
WRONG ASSUMPTION!




IF the price IS based on volumes then the assumption just used above does not work.
volume for cylinder,  {{{h*2*pi*r}}} for height h and radius r.
-
The 18-oz jar is {{{(45/4)pi}}} or about 11.25pi cubic.inch.
The 22-oz jar is {{{(3549/256)pi}}} or about 13.863pi cubic. inch.


Price of the 22-oz jar
{{{(13.863/11.25)(2.89)}}}


{{{highlight(3.56*dollars)}}}
$3.56 dollars