Hey!
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Solution:
Find 1/3 of 63.
63 / 3 = 21
21 students gave a speech today.
63 - 21 = 42
Find 2/3 of 42.
42 / 3 = 14
14 x 2 = 28
28 of the remaining students gave their speeches.
42 - 28 = 14
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Answer:
14 students haven't given their speeches!
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Hope This Helped! Good Luck!