Is the line joining the centers of two circles is their common chord?

Rachel reads 1/5 of the pages of a book plus 12 pages on the first day. on the second day, she reads 1/4 of the remaining pages plus 15 pages. on the third day, she reads 1/3 of the remaining pages plus 18 pages. on the fourth day, she reads the remaining 70 pages. how many total pages are in the book?

Ron has 8 caps and 4 of his caps are blue. thes rest of his cap are red. how many of ron's caps are red

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.