Subtract 1.5 from (4/5) of 4.5, divide the difference by 2.1, what is the quotient?
4.5的(4/5)减去1.5，所得的差再除以2.1，商是多少？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">4.5 * (4/5)</gadget>
<output>3.6</output>

<gadget id="calculator">3.6 - 1.5</gadget>
<output>2.1</output>

<gadget id="calculator">2.1 / 2.1</gadget>
<output>1</output>

<result>1</result>