A pocket contains 42 red balls, 15 yellow balls, 20 green balls, 14 white balls and 9 black balls. Ask at least how many balls must be drawn to ensure that 15 balls have the same color.
口袋里装有42个红球，15个黄球，20个绿球，14个白球，9个黑球．问至少要摸出多少个球才能保证有15个球的颜色是相同的．
<gadget id="calculator">14 * 4</gadget>
<output>56</output>

<gadget id="calculator">9 + 56 + 1</gadget>
<output>66</output>

<result>66</result>