EXHIBIT 16 POWER OF ATTORNEY Each person whose signature appears below hereby constitutes and appoints the Secretary and Assistant Secretaries of FEDERATED MDT SERIES and each of them, their true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution for them and in their names, place and stead, in any and all capacities, to sign the Registration Statement on Form N-14 relating to the proposed reorganization of Federated Technology Fund, a portfolio of Federated Equity Funds, into Federated MDT Small Cap Growth Fund, a portfolio of Federated MDT Series, and any amendments to the Registration Statement, including post-effective amendments; and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission by means of the Securities and Exchange Commission's electronic disclosure system known as EDGAR, granting unto said attorneys-in- fact and agents, and each of them, full power and authority to sign and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as each of them might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue thereof. SIGNATURES TITLE DATE /S/ John F. Donahue November 15, 2007 John F. Donahue Trustee /S/ J. Christopher Donahue November 15, 2007 J. Christopher Donahue President and Trustee (Principal Executive Officer) /S/ Richard A. Novak November 15, 2007 Richard A. Novak Treasurer (Principal Financial Officer) /S/ Thomas G. Bigley November 15, 2007 Thomas G. Bigley Trustee /S/ John T. Conroy November 15, 2007 John T. Conroy, Jr. Trustee /S/ Nicholas P. Constantakis November 15, 2007 Nicholas P. Constantakis Trustee /S/ John F. Cunningham November 15, 2007 John F. Cunningham Trustee Federated MDT Series - Power of Attorney for Merger of Federated Technology Fund into Federated MDT Small Cap Growth Fund Page 2 /S/ Lawrence D. Ellis, M.D. November 15, 2007 Lawrence D. Ellis, M.D. Trustee /S/ Peter E. Madden November 15, 2007 Peter E. Madden Trustee /S/ Charles F. Mansfield, Jr. November 15, 2007 Charles F. Mansfield, Jr. Trustee /S/ John E. Murray, Jr. November 15, 2007 John E. Murray, Jr. Trustee /S/ Thomas M. O'Neill November 15, 2007 Thomas M. O'Neill Trustee /S/ Marjorie P. Smuts November 15, 2007 Marjorie P. Smuts Trustee /S/ John S. Walsh November 15, 2007 John S. Walsh Trustee /S/ James F. Will November 15, 2007 James F. Will Trustee