S. 154 : Rectification of mistake-Mistake apparent from the record-Property held for charitable purposes-Educational institution-Net income or gross receipts-Exemption denied-Corpus donation-Final accounts reflected a loss-Matter is remanded to Assessing Officer for taking on record audited final accounts on basis of which assessee had returned income and then pass an order under section 154-Provision under section 10(23C)(iiia) did not speak of gross receipt but annual receipt which would not include voluntary contribution toward corpus, assessee is entitled for exemption of its income, including capital receipt, under section 10(23C)(iiiad). [S. 10(23C (iiia) 11(1)(d), 12A, 12AA, 143(1)(a)]