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Mechanical Comprehension on the SIFT frequently tests gear ratios, torque, and direction. For meshed gears, speed is inversely proportional to the number of teeth: NATA=NBTBN_A T_A = N_B T_B. Given NA=60N_A = 60 rpm and TA=12T_A = 12, TB=36T_B = 36. Solve NB=(NA×TA)/TB=(60×12)/36=720/36=20N_B = (N_A \times T_A)/T_B = (60 \times 12)/36 = 720/36 = 20 rpm. Meshed gears rotate in opposite directions; if Gear A rotates clockwise, Gear B rotates counterclockwise. Therefore, 20 rpm counterclockwise is correct. On SIFT items like this, confirm integer ratios and the “opposite direction” rule for external gear pairs. If the question involved belt drives or internal ring gears, direction rules differ, so always parse the setup precisely. Finally, sanity-check: the larger gear should turn slower, which matches our 20 rpm result, reinforcing the physical intuition that more teeth means fewer revolutions for the same linear tooth speed.