Answer:The answer is 10
Step-by-step explanation: lets start with 10
10 x 1= 10
10 x 2= 20
10 x 4= 40
10 x 10= 100
Then with 4
4 x 5= 20
4 x 10= 40
4 x 25= 100
Now find the number they do not have in common:
10!
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