Help me please and thanks

James is playing his favorite game at the arcade. after playing the game 3 times, he has 8 tokens remaining. he initially had 20 tokens, and the game costs the same number of tokens each time. the number tt of tokens james has is a function of gg, the number of games he plays

Which of the following is true for the relation f(x)=2x^2+1

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys