The ratio of A, B, and C is 2:5:8. The average of these three numbers is 90. What is the sum of A and B?
甲、乙、丙三个数的比是2：5：8，这三个数的平均数是90，甲数与乙数的和是多少．
<gadget id="calculator">90 * 3</gadget>
<output>270</output>

<gadget id="calculator">2 + 5</gadget>
<output>7</output>

<gadget id="calculator">2 + 5 + 8</gadget>
<output>15</output>

<gadget id="calculator">7 / 15</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">270 * (7/15)</gadget>
<output>126</output>

<result>126</result>