Final answer:
To calculate the weekly supply of formula for a newborn, multiply the ounces per feeding by the feedings per day, then by the days in a week. Convert the total ounces to cups using the conversion of 1 cup = 8 ounces. The unnecessary conversion for this problem is days per week.
Step-by-step explanation:
The student asks how many cups of formula should be in supply for a newborn for a week, given that the baby eats 6 times a day and consumes about 2.5 ounces of formula at each feeding. To begin the calculation, we multiply the ounces per feeding by the number of feedings per day, then by the number of days in a week.
Calculation Process:
- Multiply the amount of formula per feeding (2.5 ounces) by the number of feedings per day (6): 2.5 ounces/feeding × 6 feedings/day = 15 ounces/day.
- Multiply the daily amount by the number of days in a week to find the weekly formula consumption: 15 ounces/day × 7 days/week = 105 ounces/week.
- To determine how many cups are needed, we use the conversion rate of 1 cup = 8 ounces and convert ounces to cups: 105 ounces × (1 cup/8 ounces) = 13.125 cups per week.
To answer the student's question, the conversion that is not necessary for this calculation is days per week (option c) since the number of days in a week is already a given and does not require a conversion.