Guys i need your help T_T my professor gave me a problem and i don't know how to do it, pls help me

"Creat a program that will compute for the grade of students and its equivalent grade point.. the formula for computing grade is GRADE=10%, ASSIGNMENT=20%,Seatwork=30%,Quiz=40%
Note that there are 2 assignment,quiz,and seatwork given

Equivalent grade point:
1.0 = 99-100
1.25 = 96-98
1.5 = 93-95
1.75 = 90-92
2.0 = 87-89
2.25 = 84-86
2.50 = 81-83
2.75 = 78-80
3.0 = 75-77
5.0 = below 75

thanks, i hope you can help me T_T God Bless!