Uncle Zhang bought a three-year national bond of 30,000 yuan with an annual interest rate of 5.4%. How much will Uncle Zhang have in total in principal and interest when it matures?
张伯伯购买了三年期的国债30000元，年利率是5.4%，到期时，张伯伯的本金和利息共有多少元？
<gadget id="calculator">5.4 / 100</gadget>
<output>0.054</output>

<gadget id="calculator">30_000 * 0.054 * 3</gadget>
<output>4_860</output>

<gadget id="calculator">30_000 + 4_860</gadget>
<output>34_860</output>

<result>34_860</result>