Multiple myeloma is a form of cancer. In an extensive clinical trial,

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patients diagnosed as having multiple myeloma were given a certain treatment, and the subsequent number of months that each survived was recorded. Suppose that the data are summarized in the following histogram. The y axis has a range from 0-15 and the x axis has a range from 0-50. The first box has 5, the second 10, the third 15, the fourth is 15, and the fifth is 5.

Based on this histogram, estimate the standard deviation of the sample of

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survival times.

Carry your intermediate computations to at least four decimal places, and round your answer to at least one decimal place.