part a is incorrect already.

①
'He needs an extra $44 in order to buy 3 jerseys'.

This does not mean that $44 pays for 3 jerseys.

This means that he wants to buy 3 jerseys, but he doesn't have enough money. He is short of $44 to do so.


②
After receiving $108 from his father, he could buy 5 jerseys.

But recall that from part ①, he already had some money but was short of $44 to buy 3 jerseys.

So with this $108, he could take $44 out to make up that shortage to buy 3 jerseys.

Then $108 - $44 = $64

The remaining $64 is used to buy another 2 jerseys (such that he has 5 jerseys in total)


③
We can infer that $64 is the cost of 2 jerseys. So the cost of 1 jersey must be :

$64 ÷ 2 = $32

part b :

Amount of $ Clarence has at first

= cost of 3 jerseys - $44
(Remember that he was short of $44)

= 3 × $32 - $44

= $96 - $44

= $52


OR


Amount of $ Clarence has at first

= cost of 5 jerseys - $108

(Basically what we're doing here is subtracting the amount his father gave him to find, in order to find his original amount)

= 5 × $32 - $108

= $160 - $108

= $52

Thanks for your clear explanations.