Ms. Cathy bought a package of pencils. Out of every 10 pencils, 5 are black. If there are 20 pencils in the pack, what fraction of the pencils in the pack are black? What percent of the pencils in the pack are black?

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The means and mean absolute deviations of the individual times of members on two 4x400-meter relay track teams are shown in the table below. means and mean absolute deviations of individual times of members of 4x400-meter relay track teams team a team b mean 59.32 s 59.1 s mean absolute deviation 1.5 s 245 what percent of team b's mean absolute deviation is the difference in the means? 9% 15% 25% 65%