Hey!
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Writing scientific notation in numeral is solving for the equation.
Multiply 10 to 6.4 seven times.
6.4 x 10 = 64
64 x 10 = 640
640 x 10 = 6,400
6,400 x 10 = 64,000
64,000 x 10 = 640,000
640,000 x 10 = 6,400,000
6,400,000 x 10 = 64,000,000
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Hope This Helped! Good Luck!