You can solve by subtracting: 500-330
but I like to use mental math and think this way:
she has 330
70 more will give her 400
and 100 more will give her 500
100 + 70 is 170.
5 baskets...each holds 15 apples....(5 x 15) = 75 apples
4 friends pick the same amount...
4 x 75 = 300 apples picked in total. <==
The answer would be n<4 because 4 is greater than n.
I believe it's not a function because the input (x) 4 has two outputs(y), 2 and 8.