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Subjects>Math>Math & Arithmetic

If 30 times 30 equals 900 why does 29 times 31 equal 899?

Anonymous

∙ 15y ago

Updated: 9/17/2023

(x-1)*(x+1) = x2 - x + x - 1 = x2 - 1

So, when x = 30,

29*31 = 30*30 - 1

Or, since 30*30 = 900, 29*31 = 900-1 = 899

Wiki User

∙ 15y ago

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Continue Learning about Math & Arithmetic

What is the number before 900?

899

What is one less than 900?

One less than 900 is 899.

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What times 37 equals 900?

37 does not divide evenly into 900 The answer is 900/37 = 24.324

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