Xiao Ming and Xiao Qiang saved some pocket money, and the ratio of the money they saved was 5:4. During the activity to support the disaster-stricken area in Wenchuan, Xiao Ming donated 50 yuan to Beichuan Middle School, and Xiao Qiang donated 30 yuan. Equal, how much money did Xiaoqiang have?
小明和小强存了一些零用钱，他们所存钱的比是5：4，在支援汶川灾区活动中，小明向北川中学捐了50元，小强捐了30元，这时他们剩下的钱数相等，小强原来有多少钱？
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">(5/4) * 30</gadget>
<output>75/2 = around 37.5</output>

<gadget id="calculator">50 - (75/2)</gadget>
<output>25/2 = around 12.5</output>

<gadget id="calculator">(5/4) - 1</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(25/2) / (1/4)</gadget>
<output>50</output>

<gadget id="calculator">50 + 30</gadget>
<output>80</output>

<result>80</result>