In order to purify the environment, classes A and B of the sixth grade collect waste batteries in their spare time. The ratio of the number of old batteries collected by classes A and B within a week is 4:5. If 10 batteries are collected from class A and given to class B , then Class A accounts for (1/3) of the total number of the two classes. How many old batteries did Class A collect?
六年级甲、乙两班为了净化环境，利用课余时间收集废旧电池，一周内甲乙两班收集的旧电池个数比是4：5，如果从甲班收集的电池中拿出10个给乙班，那么甲班就占两班总数的(1/3)．甲班收集的旧电池有多少个？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) * 4</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">(1/3) * 5</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">4 - (4/3) - (5/3)</gadget>
<output>1</output>

<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<gadget id="calculator">4 * 10</gadget>
<output>40</output>

<result>40</result>