A $200\,\Omega $ resistor has a certain color code. If one replaces the red color by green in the code, the new resistance will be .............. $\Omega$
A$500$
B$400$
C$300$
D$100$
JEE MAIN 2019, Medium
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A$500$
a When red is replace with green $1^{st}$ digit changes to $5$ so new resistance will be $500\,\Omega $.
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