Xiao Ming and Xiao Hong read the same book. Xiao Ming reads 15 pages a day and finishes reading in 6 days. Xiao Hong reads 9 pages a day. How many days can he finish reading?
小明和小红读同一本书，小明每天读15页，6天读完，小红每天读9页，几天可以读完？
<gadget id="calculator">6 / 9</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">15 * (2/3)</gadget>
<output>10</output>

<result>10</result>