Borrowed book

Jane must as soon as possible return a borrowed book. She figured that when she read 15 pages a day return book in time. Then she read 18 pages a day and then return the book one day before. How many pages should have a book?

Result

p =  90

Solution:


15d = p
18(d-1)=p

15d-p = 0
18d-p = 18

d = 6
p = 90

Calculated by our linear equations calculator.








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