The first discounted price is given through the equation,
discounted price = ($3.45)(1 - 0.20) = $2.76
Then, due to the privilege of being a Coles-Myer discount card holder, another 7.5% discount is given. Such that the final price would be,
final price = ($2.76)(1 - 0.075) = $2.553
The total amount saved up is equal to,
$3.45 - $2.553 = $0.897
Ummmmmmmmmmmmmmmmmmmmmmmmmmmmm im sorry I don’t know but I’m guessing u add the first and add second and subtract the 11 the first and 31 second then u use that and subtract and see if it negative or positive and mark it on the dot
.3 * 18 = 5.4. 18-5.4 = 12.6$
Or
.7 * 18 = 12.6$
60=5k is the answer for your question