Answer:
You have to work backwards here
so if you had 100 dollars left and u spent 50 on a radio
100+50=150
Then You spent a 1/6 of it on stationery
So you mustve had 5/6 money left or 150 dollars
so you multiply that to find that
5/6=150/x
5x=900
x=180
so add 30 dolalrs to 150 and you have 180.
the you spent a third
you repeat the same process
the you have ur ANSWER