<PRE><B>Question 1078530</B>
x = number of minutes she spent yesterday
x + 15 = number of minutes she spend today.


the number of minutes she spent today is twice the number of minutes she spent yesterday.


x + 15 = 2x


subtract x from both sides to get 15 = x


she spent 15 minutes yesterday.


she spent 30 minutes today.


30 minutes is 15 minutes more then 15.


30 minutes is twice 15 minutes.


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