Math puzzle with six 2x2 grids, each with four labeled boxes and instructions to fill with different digits, some with "3 solutions possible."
A math puzzle featuring six 2x2 grids with numbers labeled M(7) through M(17), each grid requiring four different digits to be placed in the boxes. Some grids indicate "3 solutions possible" and a note states "all the 4 digits in each problem should be different."