Answer:
Finding 1/5 of something is the same as dividing that number by 5. Since 24 isn't divisible by 5, 24 / 5 is not an integer. Since you can't have 4.8 species of animals the answer to (a) is no.
For (b), 1/3 * 24 = 8 and 24 - 8 = 16.
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