There are several balls of red and white in the box. If one red ball and one white ball are taken out each time, when there are no red balls, there are still 50 white balls left; if one red ball and one white ball are taken out each time, There are 3 white balls, and when there are no white balls, there are still 50 red balls left. How many red balls and white balls are there in the original box?
盒子里有红、白两种颜色的球若干个，如果每次取出1个红球和1个白球，取到没有红球时，还剩下50个白球；如果每次取出1个红球和3个白球，则取到没有白球时，红球还剩下50个，原来盒子里红球和白球共有多少个？
<gadget id="calculator">50 + 50</gadget>
<output>100</output>

<gadget id="calculator">3 - 1 - 1</gadget>
<output>1</output>

<gadget id="calculator">100 / 1</gadget>
<output>100</output>

<gadget id="calculator">100 + 50</gadget>
<output>150</output>

<gadget id="calculator">100 + 150</gadget>
<output>250</output>

<result>250</result>