After a factory adopts new technology, it uses 4 tons of raw materials every day. In this way, the original raw materials used for 6 days can now be used for 9 days. How many tons of raw materials did the factory use every day?
某厂采用新技术后，每天用原料4吨．这样，原来6天用的原料，现在可以用9天，这个厂原来每天用多少吨原料？
<gadget id="calculator">9 / 6</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">4 * (3/2)</gadget>
<output>6</output>

<result>6</result>