If the mathematical signs are changed as given below, then select the option which represents the correct equation.
$$\times$$ means $$+$$
$$-$$ means $$\times$$
$$+$$ means $$\div$$
$$\div$$ means $$-$$

Option (a) $$ 18 - 25 + 30 \div7\times 11 = 19$$

After changing the signs, a new expression is formed which is given below.

$$ 18 \times 25 \div 30 - 7 + 11 = 19$$

$$ 3 \times 5 - 7 + 11 = 19$$

15-7+11 = 19

19 = 19

The given equation is satisfied and becomes the correct answer.

Option (b) $$18 + 25 - 30\div7\times 11 = 30$$

After changing the signs, a new expression is formed which is given below.

$$18 \div 25 \times 30 - 7 + 11 = 30$$

The given equation will not be true. Because it will give values in decimals.

Option (c) $$ 18 + 25 - 30 \times 7 \div 11 = 14$$
After changing the signs, a new expression is formed which is given below.

$$ 18 \div 25 \times 30 + 7 - 11 = 14$$

The given equation will not be true. Because it will give values in decimals.

Option (d) $$ 18 \div 25 + 30 -7 \times 11= 31$$

After changing the signs, a new expression is formed which is given below.

$$ 18 - 25 \div 30 \times 7 + 11= 31$$

The given equation will not be true. Because it will give values in decimals.