Answer:
The sample proportion from the sample of 900 is more likely to be close to the true population proportion, p.
Step-by-step explanation:
for the first one
Answer:

Remove backets

Group and Evaluate like terms





+1,-1 and your other would be 1,1
Answer:
3.33×10⁴
Step-by-step explanation:
You can use the hint, or you can use a common exponent. Here is the latter case.
(3.9×10⁴) -(5.7×10³) = (3.9×10⁴) -(0.57×10⁴) = (3.9 -0.57)×10⁴
= 3.33×10⁴
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With a little practice, you can see the effect on exponents of moving the decimal point. Here, we have ...
5.7×10³ = (0.57×10)×10³ = 0.57×(10×10³) = 0.57×10⁴
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When adding or subtracting in scientific notation, all that is required is that the exponents of all the numbers be the same. The hint says make all the exponents be 0. Above, we have chosen to make them all be 4. You could also use 3:
(3.9×10⁴) -(5.7×10³) = (39×10³) -(5.7×10³) = (39 -5.7)×10³
= 33.3×10³ = 3.33×10⁴
4.2 because it has a box around the corner that makes it whole