Answer:
4.47
Explanation:
What square roots are having √20 in between them?...
√16 = 4 √20 ≈ a number between 4 and 5 √25=5
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16 is 4 away from 20 25 is 5 away form 20
so √20 is closer to √16 (=4)
so a better approximation is the one closer to 4
so is 4.47