Answer:
31
Explanation:
Let h hardcover books sold and p paperbacks sold
total of 89 books, so that we can write:
h + p = 89
or p = 89 - h
Also, paperbacks cost 2 and hardcovers cost 5 for a total of 271, so we can write:
2p + 5h = 271
Now replacing first on this equation, we can solve for h:
2p + 5h = 271
2(89 - h) + 5h = 271
178 - 2h + 5h = 271
3h = 93
h = 93/3
h = 31
Hence,
31 hardcover books were sold