She started with x.
After 1 year, she had 1.025x.
She withdrew <span>£1000, so now she has 1.025x - 1000.
Then it earned interest for 1 year and ended up as </span>1.025(1.025x - 1000).
The actual amount of money was £23 517.60.
Therefore,
<span>1.025(1.025x - 1000) = 23517.60
1.025x - 1000 = 22 944
1.025x = 23 944
x = 23 360
Her original deposit was </span><span>£23 360</span>
3x=40.20.... Each book costed $13.40
