<human>:  Mariah’s grandma was teaching her to knit. Mariah used 1/4 of a skein of yarn. Her grandma used 1/2 of a skein of yarn. There are 364 yards in a skein of yarn. How many yards of yarn did they use altogether?
<bot>: How many yards of yarn did Mariah’s grandma use? ** Mariah’s grandma used 1/2 a skein of yarn. We should multiply this by (2/2) to have a common denominator, so 1/2 * 2/2 = 2/4.
How many yards of yarn did Mariah and her grandma use altogether? ** Now that there are common denominators, we can add the 1/4 skein of yarn Mariah used + 2/4 skein of yarn her grandma used = 3/4 of a skein of yarn.
How many yards of yarn did Mariah and her grandma use altogether? ** 3/4 of a skein of yarn * 364 yards = 364 / 4 = <<3/4*364=273>>273 yards.
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