(3/8)*1.67+0.33*(3/8)999*667+667.
(3/8)*1.67+0.33*(3/8)999*667+667．
<gadget id="calculator">999 * 667</gadget>
<output>666_333</output>

<gadget id="calculator">667 * 1</gadget>
<output>667</output>

<gadget id="calculator">666_333 + 667</gadget>
<output>667_000</output>

<result>667_000</result>