Thinking skills assessment

Jonathan is planning to use a 10 acre field to supply winter silage for his cattle and hay for his sheep. He reckons to get 100 bales of hay from each acre. Before cutting the hay he will first cut an acre round the edge of the field as silage - this allows him to manoeuvre his hay making machinery. After making his hay in June he will cut the whole field as second cut silage in August and again as third cut silage in September. His farm manual provides the following information:

First cut:
(As silage) 7 bales per acre
(As hay) 100 small bales per acre

Second cut:
(As silage) 5 bales per acre
(As hay) not applicable

Third cut:
(As silage) 4 bales per acre
(As hay) not applicable

How many bales of silage will Jonathan have at the end of his harvest?
A) 16
B) 90
C) 97
D) 157
E) 160


The wording of this question is strange, i believe they mean that in the second and third cut the whole field will have no hay, and only silage.
First cut = 7 * 1 = 7 bales of silage and 100 * 9 = 900 bales of hay
Second cut = 5 * 10 = 50 bales of silage and 0 bales of hay
Third cut = 4 * 10 = 40 bales of silage and 0 bales of hay

So the final amount of silage cut is 7+50+40=97 bales of silage

Hope this helps!