A and B share several stamps. It is known that A's stamps account for 3/7 of the total. If B gives A 10 stamps, the number of stamps is equal. How many stamps do A and B share?
甲、乙共有邮票若干张，已知甲的邮票数占总数的(3/7)，若乙给甲10张，则两人的邮票数相等，甲、乙两人共有邮票多少张．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(1/2) - (3/7)</gadget>
<output>1/14 = around 0.071429</output>

<gadget id="calculator">10 / (1/14)</gadget>
<output>140</output>

<result>140</result>