Earning in the remaining 8 months = 8000 × 8 = ₹ 64000 Earning in March, May, July, December (4 months) = (8000 × 7/4) × 4 = ₹ 56000 ⇒ Total earnings (12 months) = 64000 + 56000 = ₹ 120000 Savings in the remaining 8 months = 6000 × 8 = ₹ 48000 Savings in March, May, July, and December (4 months) = (6000 × 3/2) × 4 = ₹ 36000 ⇒ Total savings (12 months) = 48000 + 36000 = ₹ 84000 ∴ Total expenditure (12 months) = 120000 - 84000 = ₹ 36000 ⇒ Average expenditure per month = 36000/12 = ₹ 3000