How many 1/4 teaspoon doses are in 7/8 teaspoon of medicine

Suppose a man is heterozygous for heterochromia, an autosomal dominant disorder which causes two different‑colored eyes in an individual, produced 25‑offspring with his normal‑eyed wife. of their children, 15 were heterochromatic and 10 were‑normal. calculate the chi‑square value for this observation.

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Add the two expressions 3.8b - 7 and 2.9b + 9 enter your answer in simplified form