Cheryl ate 7 m&m's after lunch. She ate 5 m&m's after dinner, and she gave some to her sister. If Cheryl had 25 m&m's at the beginning, how many did she give to her sister?
Cheryl at 7 + 5 = <<7+5=12>>12 m&m's
She gave 25 - 12 = <<25-12=13>>13 m&m's to her sister.
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