Cheryl has to pay a total charge of £100.98.
Explanation:
Step 1; A ticket for an adult costs £12 and a ticket for a child costs £6. So for 6 adults and 3 children, the ticket price is
Ticket price= 6 × £12 + 3 × £6 = £72 + £18 = £90.
So the ticket prices alone are £90. A booking fee of 10% is added to this £90.
Booking fee = 10% of £90 = £9.
Ticket price inclusive of booking fee = £90 + £9 = £99.
Step 2; Cheryl pays by credit card so an additional 2% is added to the final price i.e. 2% is added to the £99.
Credit card charges = 2% × £99 = £1.98
Final booking fee = £99 + £1.98 = £100.98.
So buying the tickets with credit card, Cheryl pays £100.98 to buy the tickets.