The weight of the original salt in the bottle is (1/10) of the water, and after adding 40 grams of salt, the weight of the salt accounts for (1/7) of the salt water. How many grams of the original salt water in the bottle?
瓶内原有盐的重量是水的(1/10)，加进40克盐后，盐的重量占盐水的(1/7)．瓶内原有盐水多少克？
<gadget id="calculator">7 - 1</gadget>
<output>6</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/6) - (1/10)</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">40 / (1/15)</gadget>
<output>600</output>

<gadget id="calculator">600 * (1/10)</gadget>
<output>60</output>

<gadget id="calculator">600 + 60</gadget>
<output>660</output>

<result>660</result>