We can calculate (62 + 90) / 2 = 76. it's <span>known that 95% lies between the mean and twice the standard deviation. </span><span>if the mean is "μ" and the standard deviation is "σ": </span><span>μ-2σ and μ+2σ. i</span><span>f μ=76, then </span><span>76+2σ = 90, so 2σ = 14, so σ = 7.
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<span>the mean is 76 and the standard deviation 7. </span>
8-4x=9
-4x=9-8
-4x=1
X=-1/4
X=-0.25
The answer is A, make sure to combine like terms
Answer:
b
Step-by-step explanation:
because i took the test
