A. (6*10000)+(2*1000)+(7*10)+(1*1)+(9* 1/100)
You simply multiply the number by is value placement so, since 6 is in the 10,000's place, you multiply 6 by 10,000. Since 2 is in the 1,000's place, multiply 2 by 1,000. Since 7 is in the 10's place, multiply 7 by 10. And so on.
Hope this helps!
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