Answer:
7 fancy shirts and 5 plain shirts
Explanation:
f and p are the numbers of fancy and plain shirts
f+p = 12
p = 12-f
20f + 10p = 190
20f + 10(12-f) = 190
20f + 120 - 10f = 190
10f = 70
f = 7
p = 12-f = 5
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