The brain of a 3-year-old child weighs about 1000 grams, which is (5/7) that of an adult's brain. How many grams does an adult human brain weigh?
3岁儿童的大脑重大约1000克，是成年人大脑重的(5/7)．成年人的大脑重约是多少克？
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">1_000 / (5/7)</gadget>
<output>1_400</output>

<result>1_400</result>