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put this solution on YOUR website!To find the number of elements in the set K U J, simply add the two sets together. However, remember to subtract the number of elements in both sets (since these elements are repeated)
In other words, use this formula:
n ( K U J) = n(K) + n(J) - n(K ∩ J)
In this case, n(K)=30, n(J)=46 and n(K ∩ J) = 11. Plug these values in to get:
n ( K U J) = 30 + 46 - 11
Add
n ( K U J) = 76 - 11
Subtract
n ( K U J) = 65
So there are 65 elements in set K U J