Which two digits need to be interchanged to make the following equation correct?
$$16 \div 7 \times 2 + 4 − 3 = 12$$

Option (a) 2 and 4

$$16 \div 7 \times 4 + 2 − 3 = 12$$

$$\frac{16}{7}\times4+2−3=12$$

The above-given equation is not satisfied. Because it will give values in fractions. So this is not the correct answer.

Option (b) 7 and 4

$$16 \div 4 \times 2 + 7 − 3 = 12$$

$$\frac{16}{4}\times2+7−3=12$$

$$4\times2+7−3=12$$

$$8+7−3=12$$

12 = 12

The above-given equation is satisfied. So this is the correct answer.

Option (c) 16 and 2

$$2 \div 7 \times 16 + 4 − 3 = 12$$

$$\frac{2}{7}\times16+4−3=12$$

The above-given equation is not satisfied. Because it will give values in fractions. So this is not the correct answer.
Option (d) 7 and 3

$$16 \div 3 \times 2 + 4 − 7 = 12$$

$$\frac{16}{3}\times2+4−7=12$$

The above-given equation is not satisfied. Because it will give values in fractions. So this is not the correct answer.