Answer:
a) 490
b) 240
Step-by-step explanation:
b) It is convenient to answer part B first.
The number owning only a fax will be the number owning a fax less the number that own both a fax and a copier:
420 -180 = 240 . . . . number owning only a fax
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a) The number owning one or the other will be the number owing a copier (which includes those owning both) plus the number owning only a fax:
250 +240 = 490 . . . . number owning either
_____
If you want to work part A first, then you need to use the relation ...
n(A∪B) = n(A) +n(B) -n(A∩B)
Answer:
0.789
Step-by-step explanation:
First, find the expected value (the mean).
μ = ∑ x P(x)
μ = (0) (0.359) + (1) (0.436) + (2) (0.180) + (3) (0.025)
μ = 0.871
Next, find the variance.
σ² = ∑(x − μ)² P(x)
σ² = (0 − 0.871)² (0.359) + (1 − 0.871)² (0.436) + (2 − 0.871)² (0.180) + (3 − 0.871)² (0.025)
σ² = 0.622
Finally, find the standard deviation:
σ = √0.622
σ = 0.789
Answer:
a. 
Step-by-step explanation:

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This is a tricky question that Reina and Sam are multiplying (84)5 (73)9and their work are (84)5 (73)9 = 84 + 573 + 9 = 89712 Reina's(84)5 (73)9 = 84⋅573⋅9 = 820727 Sam'sActually they are doing or multiplying using exponents.
Reina’s work (8⁴)₅(7³)⁹=8⁴⁺⁵+ 7³⁺⁹= 8⁹ 7¹²This is incorrect because she added exponents instead of multiplying exponents
Sams work (8⁴)⁵ (7³)⁹=8⁴ˣ⁵ 7³ˣ⁹= 8²⁰ 7²⁷This is correct because Sam multiplied exponents correctly
Exponents are multiplied not added.
The answer is 5.50$ you have to divide 16.50/ 3