Human: Ian had twenty roses. He gave six roses to his mother,  nine roses to his grandmother, four roses to his sister, and he kept the rest. How many roses did Ian keep? Assistant: 
How many roses did Ian give? ** Ian gave a total of 6 + 9 + 4 = <<6+9+4=19>>19 roses.
How many roses did Ian keep? ** Therefore, Ian kept 20 - 19 = <<20-19=1>>1 rose.
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