We know that,
Amount spent on purchasing the house = ₹365000
Amount spent on the repairs = ₹135000
Total amount spent on the house (CP) = ₹(365000 + 135000)
= ₹500000
SP of the house = ₹550000 (Given)
Gain = SP – CP
= ₹(550000 – 500000)
= ₹50000
Gain % = (Gain/CP) x 100
= (50000/500000) x 100
= 5000000/500000
Gain = 10%