Answer:
1p 2p 2p 2p 5p 5p 10p
Explanation:
Available coins that are less than 11p: 1p 2p 5p 10p
11p with two coins ⇒ 1p + 10p only
11p with three coins ⇒ 1p + 5p + 5p only
11p with three coins ⇒ 2p + 2p + 2p + 5p only
Therefore, the seven coins that Luke has are:
1p 2p 2p 2p 5p 5p 10p