Let say the number is 0.5
Then, sum of this number will be 0.5+0.5=1
Now two is twice of 1.
Hence, it proved to be correct.
And difference between 5 and 1 is 4 which is less than 12. It also match the question condition.
Answer: The number is 1.
Step-by-step explanation:

While subtracting , the sign of each term of second expression changes & remove the parentheses.
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Combine like terms. Like terms are those which have the same base. Only coefficients of like terms can be added or subtracted.
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In standard from , the expression should be written in such a way that the power of variables goes from highest to lowest.

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|3x+1|=4 : x=−
5
3 or x=1
Pasos
|3x+1|=4
Aplicar las propiedades de los valores absolutos: Pi |u| = a, a>0 entonces u = a or u = −a
3x+1=−4 or 3x+1=4
Mostrar pasos
3x+1=−4 or 3x+1=4
Bill has 50 pennies in his drawer he finds 4 more pennies on the floor and his brother gives him x times the amount of pennies he has.