I’m pretty sure there’s not enough informatio, what did she start with? A better problem would be ”Lucy started with $15 dollars. She spent 3/5 of her money on a hand bag, she then spent the remainer on 3 shirts that cost $4 each. How much did her handbag cos?” then we would add 3+4 which equals 7 then count how much till we get to $15 (the money which she starts with) then we would know that that hand bag cost $8 (7+8=15)
