In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Monsoons coming every three to _ years can add almost a foot of water to the mountain's surface.

Answer: seven

Question: Most children start to get their adult teeth at about _ years of age.

Answer: six

Question: Illness appears an average of _ weeks after a person eats contaminated food.

Answer:
three