Idon't understand this word problem.

Hello! So here what they are saying basically is, Jon has an allowance that is 100% of some amount. We want to know this amount from the given data. Here’s a list of what we have

1/3 of x spent on cards
1/4 of x spent on souvenirs
3/8 of x spent on ticket
$5 leftover

So Jon used 1/3x+1/4x+3/8x+5=x by finding LCD or Lowest Common Denominator;

8/24x+6/24x+9/24x+5=24/24x
23/24x+5=x
5=1/24x
x=24*5
x=$120

Therefore Jon had $120 in allowance and he used;
$40 on cards
$30 on souvenirs
$45 on ticket
$5 leftover

Total = 40+30+45+5=120

Hope this helped out. Any questions please just ask. Thank you.