I have 15 orange sweets and 10 yellow sweets 1 gets taken out of the packet, what is the probability that the sweetis:
(A) orange
(B) yellow

You have 15 orange sweeties and 10 yellow sweeties, for a total of 25 sweeties. Probability can be thought as "favorable cases on total cases".

(A) Sweetie is orange: favorable cases 15 as you have 15 orange sweeties, total cases 25, thus probability 15/25

(B) Sweetie is yellow: similarly, 10 favorable cases on 25 total cases, thus probability 10/25