Explanation; First you need to find 2/5 of £4283.30 which is £1713.32. This represents or shows how much money she has left after her bills. Now minus £19.99+£12.99 (this shows the money she spent on the two shirts and sunglasses) This leaves Selena with £1680.34
Equation in full; 2/5 / £4283.30 = £1713.32 £1713.32-(£19.99+£12.99)=£1680.34