From the school library

Dear reader, thank you for borrowing three books from the school library. Together they have three hundred and sixty pages: one of one hundred and twenty, one of one hundred and fifty, and one of ninety.

Dear reader, you borrowed $3$ books: $120+150+90=360$ pages.

$120+150+90=360$ pages.

You may keep them for fourteen days. After that, please bring them back, or ask us to renew them.

You may keep them $14$ days; then return or renew them.

Time allowed: $t=14$ days.

Three hundred and sixty pages in fourteen days is about twenty-six pages a day, so a short time every evening is enough. That is fewer than thirty pages a day.

$360÷14\approx 25.7$, so $26$ pages a day is enough, fewer than $30$.

$360÷14\approx 25.7$, and $25.7<26<30$.

If you read twenty-six pages a day, you will finish on the very last day. If you read thirty, you will finish two days early. Happy reading, the school librarian.

At $26$ a day: $26\times 14=364\ge 360$, finished on the last day. At $30$ a day: $360÷30=12$ days, so $14-12=2$ days early. Happy reading, the school librarian.

$26\times 14=364\ge 360$, and $360÷30=12$, so $14-12=2$.