Put 7 red balls and 3 blue balls in a box, let you draw 1 ball out of it each time, and then put it back, so that you touch 3 times in total, what is the probability of getting blue balls?
把7只红球和3只蓝球放在一个盒子里，让你每次从中摸出1只球，然后再放回去，这样共摸3次，摸到蓝球的可能性是多少．
<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>