Add 20 kilograms of water per kilogram of type A pesticide, and 40 kilograms of water per kilogram of type B pesticide. Now, in order to improve the efficacy, according to the opinion of the Institute of Agricultural Sciences, two kinds of pesticides, A and B, are used in combination. If 140 kilograms of water is to be mixed, how many kilograms of pesticide is there in it?
甲种农药每千克兑水20千克，乙种农药每千克兑水40千克，现在为了提高药效，根据农科所意见，甲、乙两种农药混合使用，已知两种农药共5千克，要兑水140千克，则其中甲种农药有多少千克．
<gadget id="calculator">5 * 40</gadget>
<output>200</output>

<gadget id="calculator">200 - 140</gadget>
<output>60</output>

<gadget id="calculator">40 - 20</gadget>
<output>20</output>

<gadget id="calculator">60 / 20</gadget>
<output>3</output>

<result>3</result>