Plant peony flowers at the largest and equal distance on the sides of the rectangular flowerbed with a length of 48 meters and a width of 42 meters, and plant three roses between every two peony flowers. How many roses were planted in total?
在长48米，宽42米的长方形花圃周围的边上以最大并且相等的距离栽上牡丹花，每两棵牡丹花之间栽3棵月季花．一共栽多少棵月季花？
<gadget id="calculator">48 / 6</gadget>
<output>8</output>

<gadget id="calculator">42 / 6</gadget>
<output>7</output>

<gadget id="calculator">8 + 7</gadget>
<output>15</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">30 * 3</gadget>
<output>90</output>

<result>90</result>