Lara surveyed all of the 11^{\text{th}}11 th 11, start superscript, start text, t, h, end text, end superscript grade students at her school about the number of languages they speak and whether or not they have allergies. Round your answers to the nearest tenth of a percent.

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in counting the number of heads in 4 coin flips, the probability that we get exactly one head is the probability that we get anyone of the following 4 outcomes: httt, thtt, ttht, or ttth. each has probability 1/16, so the probability to get exactly one head in 4 flips is 1/16 + 1/16 + 1/16 + 1/16 = 4/16 = 1/4.