The equation 20 + 30 × 0 + 1 is a simple order-of-operations puzzle. Multiplication comes before addition, so begin with 30 × 0. That equals 0. The equation then becomes 20 + 0 + 1. Adding those remaining numbers gives 21.
The correct answer is 21.
The mistake many people make is adding 20 and 30 before doing the multiplication. That changes the intended order and produces the wrong result. Another easy mistake is forgetting the final +1 after multiplying by zero.
The safest method is to solve multiplication and division first, then complete addition and subtraction from left to right. Once the multiplication is handled, this puzzle becomes very easy. If you got 21, you followed the standard order correctly.
