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How to translate word sentence into algebra expression and write one variable equation?

Question:

A store received 3000 bags of flour on the first day, 25% of which is unbleached flour. The next day another batch of unbleached flour arrived. At this time unbleached flour account for two-thirds of the total flour. How many bags of unbleached flour were arrived on the next day?

Solution:

Let x be the unbleached flour arrived on the next day.
First day unbleached flour = 25% × 3000
Next day unbleached flour = x
Total unbleached flour = x + 25% × 3000
Total flour = 3000 + x
The relationship is: total unbleached flour is equal to two-thirds of the total flour.
x + 25% × 3000 = (2/3) (3000 + x)
x + 750 = (2/3) (3000) + (2/3) x
x - (2/3) x = 2000 - 750
(1/3) x = 1250
x = 3 × 1250 = 3750

There are 3750 bags of unbleached flour were shipped to the store on next day.