Grandpa bought a pair of glasses with a 30% discount, which is 30 yuan cheaper. What is the original price of the glasses?
爷爷买了一副眼镜打七折，便宜了30元，眼镜的原价为多少元．
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">30 / (3/10)</gadget>
<output>100</output>

<result>100</result>