B u A = 48
B = 45
The part of set B not included in A is B - A∩B = 45 - 7 = 38
Since B u A = 48, A must have 48-38 = 10 elements (3 exclusive of B, 7 shared with B).
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Alternatively, the inclusion-exclusion principle may be used: A + B - (A ∩ B) = A u B
A + 45 - 7 = 48
A = 48 - 45 + 7
A = 10
NOTE that I'm using A and B to indicate the number of elements in each set, respectively.
More formally, one would write |A| and |B| to indicate the cardinality (number of elements) of the set.
Answer:
1
Step-by-step explanation:
The range is the difference between the largest and smallest values.
range = 9 - 2 = 7
If 2 is replaced by 3 then 3 becomes the smallest value and
range = 9 - 3 = 6
That is the range decreases by 1
Answer:
$1400
Step-by-step explanation:
x= profit of 6th month
(200+300+400+500+500+x)
-------------------------------------- = 550
6
(1900+x)=3300
x=3300-1900
x=1400
