Let white marbles = x
Purple marbles = 5x + 2
Given:
x + 5x + 2 = 104
6x = 102
x = 17
Purple marbles = 5(17) + 2 = 85 + 2 = 87
This is a strange question, and f(x) may not even exist. Why do I say that? Well..
[1] We know that f(a+b) = f(a) + f(b). Therefore, f(0+0) = f(0) + f(0). In other words, f(0) = f(0) + f(0). Subtracting, we see, f(0) - f(0) = f(0) or 0 = f(0).
[2] So, what's the problem? We found the answer, f(0) = 0, right? Maybe, but the second rule says that f(x) is always positive. However, f(0) = 0 is not positive!
Since there is a contradiction, we must either conclude that the single value f(0) does not exist, or that the entire function f(x) does not exist.
To fix this, we could instead say that "f(x) is always nonnegative" and then we would be safe.
We have that 3 pencils cost $0.35, and 2 dozen pencils are 24 pencils, then we divide by 3 to know how many 3-pencils combo we can get:
therefore, 2 dozen pencils would cost $2.8
The 60th visit because you have to look for the first same number in a list of the multiples of 12 and 15:)