Mom bought 15 kilograms of rice and 5 kilograms of flour at the grain store, paid the salesperson 50 yuan, and got back 19 yuan. Knowing that flour is 2 yuan per kilogram, how much is rice worth per kilogram?
妈妈在粮店买了15千克大米和5千克面粉，付给售货员50元，找回19元，已知面粉每千克2元，大米每千克值多少元？
<gadget id="calculator">2 * 5</gadget>
<output>10</output>

<gadget id="calculator">50 - 19 - 10</gadget>
<output>21</output>

<gadget id="calculator">21 / 15</gadget>
<output>7/5 = around 1.4</output>

<result>7/5 = around 1.4</result>