The average of four consecutive odd numbers is 78. What is the largest of these four numbers?
四个连续奇数的平均数是78，这四个数中最大的一个是多少．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">78 * 4</gadget>
<output>312</output>

<gadget id="calculator">2 + 4 + 6 + 312</gadget>
<output>324</output>

<gadget id="calculator">1 + 1 + 1 + 1</gadget>
<output>4</output>

<gadget id="calculator">324 / 4</gadget>
<output>81</output>

<result>81</result>