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Sam and Sal are making a Valentine's poster for their mother. They need 8/10 of a yard of ribbon to complete the poster. Sam has 3/10 of a yard. Sal has 58/100 of a yard. Their cousin, Randy, has twice the amount of ribbon as Sam. Does Randy have enough to complete the poster by himself? How do you know?
No, Randy does not have enough. He only has 6/10 (3/10 x 2). He still need 2/10 more to equal 8/10 of a yard.