Amon & Rhonda combined have 215 marbles. If Amon owns 55 marbles more than Rhonda, how many marbles does Rhonda have?
Let's say Rhonda has m marbles.
The total number of marbles that Ammon has is m+
<gadget id="calculator">+55</gadget>
<output>55</output>
55.
Amon &amp; Rhonda combined have m+(m+55) = 215.
This means the total number of marbles they have together is 2m+55 = 215
2m=215-55.
The total number of marbles that Rhonda has is m=160/2.
Rhonda has m=80 marbles.

<result>80</result>