Does a machine that takes one quarter at a time into its input and produces two gumballs in its output act like a function?

Yes, because for a function the output should always be the same for the same input.

So when you input 1 quarter you always get 2 gumballs. ( the number of gumballs is always 2 and doesn't change).

(1,4) is on graph of f(x)

f(1) = 4

so 1/4 f(x)

1/4 f(1)

1/4. ×4

1

so point for function 1/4. f(x) is (1,1)

26 is 33.33% of 78

step-by-step explanation:

26 is what percent of 78?

26 is p% of 78

equation: y = p% * x

solving our equation for p

p% = y/x

p% = 26/78

p = 0.3333

convert decimal to percent:

p% = 0.3333 * 100 = 33.33%