Step-by-step explanation:
The answer is f + 18 = 108 f = 90
The question states that a number increased by 18 is 108, which means that the problem involves addition, so option 3 and 4 cannot be the answer because they involve division and multiplication. Since a number increased by 18 is equal to 108, you can subtract 18 from 108 to find the value of f, which is 90
