Phyllis read 4 pages of a storybook on the first day. She read 7 pages on the second day, 10 pages on the third day ....
If it took her 10 days to finish reading the storybook, how many pages were there in the storybook?
4, 7, 10, 13, 16, 19, 22, 25, 28, 31 35 × 5 = 175
There were 175 pages in the storybook.