The annual interest rate of the bank's one-year savings is 2.25%. When Xiao Wang withdraws the principal and interest due in one year this year, he pays interest tax of 4.5 yuan. How much is the principal that Xiao Wang deposited in the bank a year ago?
银行一年期储蓄的年利率为2.25%，小王今年取出一年到期的本金和利息时，缴纳了利息税4.5元，则小王一年前存入银行的本金为多少元？
<gadget id="calculator">2.25 / 100</gadget>
<output>0.0225</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">0.0225 * (1/5)</gadget>
<output>0.0045</output>

<gadget id="calculator">4.5 / 0.0045</gadget>
<output>1_000</output>

<result>1_000</result>