If the recipe requires 1/2 cup of peaches and you need to find how many fourth cups of peaches are used to make one half cup, you just need to do some division.
To begin, take 1/2÷1/4 and find the reciprocal of 1/4 (the divisor) and get 1/2×4/1.
*note: when you get the reciprocal of the divisor you also change the division into multiplication.*
Finally when you multiply 1/2×4/1 you get 4/2 which simplifies to 2/1 fourth cups or just two. (I simplified the fraction by dividing both the numerator and the denominator by 2)