Presumably, the coin tosses are independent of one another, so

But if the coin flips are not independent, then we can't really say anything about this probability without any more information about how the flips are related...
35 ÷ 7 = 5
So the money is going to double 5 times.
300 = 600
600 = 1,200
1,200 = 2,400
2,400 = 4,800
4,800 = 9,600
So she would have $9,600 at the end.
Hope it helps!
Aight so first you need to isolate the y. Simply add 8 to both sides and now you have 1/4y = 33. Now divide both sides by 1/4 (which is the same by multiplying by 4) and you get 132