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Re: The average (arithmetic mean) of 5, 25, and 45 is 10 more than the ave
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27 Sep 2022, 06:59
The average of 5, 25, and 45 is:
(5 + 25 + 45) / 3 = 75/3 = 25
25 is 10 more than 15, which gives us the average involving our unknown amount:
(10 + 30 + x) / 3 = (40+x)/3 = 15
==> 40+x = 45
==> x = 5
Answer A.