Antoinette weighs 7 less kilograms than twice Rupert's weight. Together they weigh 98 kilograms. How many kilograms does Antoinette weigh?
Let R = Rupert's weight.
Antoinette = 2R - 7.
R + 2R - 7 = 98
3R = 105.
Rupert = 
<gadget id="calculator">35</gadget>
<output>35</output>
35 kg.
Antoinette = 2 * 35 - 7 = 
<gadget id="calculator">2*35-7</gadget>
<output>63</output>
63 kg.
Antoinette weighs 63 kilograms.

<result>63</result>