Answer:
<h2>Island A, B and C has 10, 5 and 7 houses respectively.</h2>Step-by-step explanation:
Let, the three islands A, B and C has a, b and c houses respectively.
According to the question, a + b = 15; a + c = 17; b + c = 12; a + b + c = 22.
Adding [ a + b = 15; a + c = 17]-these two, we get, .
Now, .
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