Which two signs and two numbers should be interchanged to make the given equation correct?
$$45 - 87 \times 20 \div 5 + 29 = 50$$

Option (a) $$20\ and\ 29,\div\ and\ \times$$

$$45-87\div29\times5+20=50$$

$$45-3\times5+20=50$$

45-15+20=50

30+20=50

50=50

The given equation is satisfied. So this will be the correct answer.

Option (b) $$29\ and\ 45,+\ and\ \div$$

$$29-87\times20+5\div45=50$$

$$29-87\times20+\frac{1}{9}=50$$

The given equation is not satisfied. Because it will give value in the fraction. So this will not be the correct answer.

Option (c) $$20\ and\ 29,\div\ and\ +$$

$$45-87\times29+5\div20=50$$

$$45-87\times29+\frac{1}{4}=50$$

The given equation is not satisfied. Because it will give value in the fraction. So this will not be the correct answer.

Option (d) $$45\ and\ 5,\ \times\ and\ -$$

$$5\times87-20\div45+29=50$$

$$5\times87-\frac{4}{9}+29=50$$

The given equation is not satisfied. Because it will give value in the fraction. So this will not be the correct answer.