The water level in a lake was 12 inches below normal at the beginning of march. The water level decreased 2 1/4 inches in march and increased by 1 5/8 inches april. What was the water level compared to normal at the end of april? Explain how you solved his question

This can be solve by simple addition and subtraction. Since the initial water in the lake is 12 in below the normal starting by march, and it decreased further by 2 ¼ in by the end of march and increased by 1 5/8 in by the end of april. So the net water level is

L = 12 - 2 ¼ + 1 5/8 = 12 5/8 in below the normal