Answer:
R / 2
Explanation:
According to Ohm law, the current flowing within the resistor is the ratio between the potential difference and the resistance:
[tex]I = \frac{V}{R}[/tex]
So if wire A carries twice the current of wire B, while their potential is the same then:
[tex]I_A = 2I_B[/tex]
[tex]\frac{V}{R_A} = \frac{2V}{R_B}[/tex]
[tex]R_B = 2R_A[/tex]
[tex]R_A = R_B / 2 = R / 2[/tex]
