The bag contains 10 beads of different colors, 100 of each. If you want to ensure that 3 beads of different colors are drawn from the bag and at least 10 of each are drawn, then at least how many beads must be drawn.
袋中装有10种不同颜色的珠子，每种都是100个．要想保证从袋中摸出3种不同颜色的珠子并且每种至少10个，那么至少要摸出多少个珠子．
<gadget id="calculator">100 * 2</gadget>
<output>200</output>

<gadget id="calculator">9 * 8</gadget>
<output>72</output>

<gadget id="calculator">200 + 72 + 1</gadget>
<output>273</output>

<result>273</result>