Using a very precise measuring device, Dr. Calvin measured the thickness of a piece of metal to be 0.00064 of a meter. Dr. Amos measured another piece to be 2.5 × 10-5 of a meter thick.
If the doctors put the two pieces of metal on top of each other, the new piece of metal would be × 10-4 of a meter thick.

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Question

Using a very precise measuring device, Dr. Calvin measured the thickness of a piece of metal to be 0.00064 of a meter. Dr. Amos measured another piece to be 2.5 × 10-5 of a meter thick. 
If the doctors put the two pieces of metal on top of each other, the new piece of metal would be  × 10-4 of a meter thick.
    
Really need answer

mathmale · Answer

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