Answer:
25%
Explanation:
1) They bought the house for $120,000 and sold it for $150,000 whcich is simply 150,000/120000 simplified is 5/4.
2) In order to get it as a percentage you multiply the 5/4 by 100 getting 125. To work out the percentage increase you do 125-100 = 25% making the percentage increase 25%
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