Answer:
in 6 days he read p/12
Step-by-step explanation:
In the last 20 days, he read 20/6 * p/12 = 20p/72 = 5p/18
So, 312 = 13p/18; p = 432
starting with 432 pages, he read 312, leaving 120
During each of the 20 days, he read 6 pages
In 6 days he read 36 pages, which is 432/12
