Kathleen's allowance in middle school was $8 + $2 = $<<8+2=10>>10.
Twice her middle school allowance is $10 x 2 = $<<10*2=20>>20.
So, Kathleen's senior year allowance is $20 + $5 = $<<20+5=25>>25.
Her allowance increased by $25 - $10 = $<<25-10=15>>15.
Kathleen's percent increase in her weekly allowance is $15/$10 x 100% = <<15/10*100=150>>150%.
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