The phrase "average of two days" is correct and usable in written English.
It can be used when discussing a calculation or comparison involving the duration or data from two specific days.
Example: "To find the average of two days, we need to add the total hours worked and divide by two."
Alternatives: "mean of two days" or "midpoint of two days".
Four engineers each take an average of two days per problem, so every day the queue of unsolved problems grows by one.
If the condition requires physiotherapy, staff are given an appointment within an average of two days.
It lasted an average of two days of use with the screen on all the time and a dark face.
Warmer-water species are marching poleward, much as creatures are on land, where butterflies have been shifting ranges northward about 6 kilometers per decade, and amphibians and migratory birds are breeding an average of two days earlier.
He works an average of two days a week, and cannot work more, he said, because the ligaments in his knees have been torn and he has difficulty walking.
Small and medium-sized companies (SMEs) in Uzbekistan surveyed by the International Finance Corporation, part of the World Bank group, reported that they had to endure an average of 6.5 inspections in a single year, each lasting an average of two days.
Here he will treat every 8th day and feed the treated straw for an average of seven days starting from the 4th day after treatment (Table 2b).
Baseline data for body weight, food and water consumption were summarized as the average of three days and compared with each day after laparotomy/anesthesia for each individual.
Each female was tested only once each day, and all three trials were completed within an average of five days and a maximum of eight.
In the United States, it's an average of six days and six procedures.
(His association's clients spend an average of $6,000 a person for trips that last an average of seven days).
