Answer:
[tex] \large{ \boxed{12\%}}[/tex]
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[tex] \large{ \tt{G \: I \: V \: E \: N}} : [/tex]
[tex] \longrightarrow{ \tt{}}[/tex] Commission received : $ 480
[tex] \longrightarrow[/tex] Selling price of merchandise : $ 4000
[tex] \large{ \tt{ To \: Find : }}[/tex]
[tex] \longrightarrow[/tex] Commission rate
[tex] \large{ \tt{SOLVING : }}[/tex]
[tex] \star \: \large{ \tt{x\% \: of \: 4000 = 480}}[/tex]
[tex] \longrightarrow \: { \tt{ \frac{x}{100} \times 4000 = 480 }}[/tex]
[tex] \longrightarrow{ \tt{40x = 480}}[/tex]
[tex] \longrightarrow{ \tt{x = \frac{480}{40} }}[/tex]
[tex] \longrightarrow{ \tt{x = 12\%}}[/tex]
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