The number to be added to $$89.376$$ to get $$1000$$
Subtract $$89.376$$ from $$1000$$
Convert the decimals into like decimal numbers
Like decimals are $$89.376$$ and $$1000.000$$
$$1000.000$$
$$–$$ $$89.376$$
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$$910.624$$
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Therefore, the number to be added to $$89.376$$ to obtain $$1000$$ is $$910.624$$