What is the sum of all odd numbers from 1 to 2019?

1-3-5-7-9-11-13-15-17-19-21 and more

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.

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