min number/max number

i have a query

i have a sum that would look look this C12-C16
but i want it to be a minimum of 22 left :-

ie

overs bowled =C12 45

minutes lost =C15 ??

overs lost = C16 C15/3.5 (this total should be no more than 23)

revised overs = C18 C12-C16 (this total depending on the sum of C16 should be no less than 22)

how would i write it

thanks

cliff