Question 202088
Try this:
For each aircraft (A) there are four submarines (4S) for a total of five weapons (5W).
Which of the four choices of answers is evenly divisible by five?
Just one of them, that's 35 or answer 1.
If you have to show this algebraically, then let W = number of weapons.
From the problem description, you have W = 1A and 4W = 4S, so...
W + 4W = 5W
Which answer is a multiple of 5?