When two numbers are divided, the quotient is 15 and the remainder is 5. The sum of the dividend, divisor, quotient and remainder is 313. What is the dividend?
两数相除商15余5，被除数、除数、商、余数之和为313，被除数是多少．
<gadget id="calculator">313 - 5 - 15 - 5</gadget>
<output>288</output>

<gadget id="calculator">15 + 1</gadget>
<output>16</output>

<gadget id="calculator">288 / 16</gadget>
<output>18</output>

<gadget id="calculator">18 * 15</gadget>
<output>270</output>

<gadget id="calculator">270 + 5</gadget>
<output>275</output>

<result>275</result>