Answer:
2 small boxes sent and 4 large boxes sent.
Explanation:
Let the number of small boxes be S and the number of large boxes by L
Given that there were 2 more large boxes sent than small boxes, then
L = S + 2
Also given that each small box can hold 30 books and each large box can hold 55 books and altogether can hold 280 books.
30S + 55L = 280
Solve both equations simultaneously
30S + 55(S + 2) = 280
85S + 110 = 280
85S = 280 - 110
85S = 170
S = 170/85
S = 2
Since L = S + 2
L = 2 + 2 = 4
The number of small boxes sent and the number of large boxes sent are 2 and 4 respectively.