Math Misconception Test

Is 9.11 Greater Than 9.9?

No, 9.11 is not greater than 9.9.
9.9 is greater than 9.11.

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Why? A Step-by-Step Explanation

To compare decimals, we examine the digits from left to right, starting with the largest place value.

1. Compare the whole numbers (the part before the decimal):

• Both numbers have a whole number part of 9.
  → They are equal so far. We must look at the decimal parts.

2. Compare the first decimal place (tenths place):

• 9.11 has 1 in the tenths place (the "1" in "9.11").
• 9.9 has 9 in the tenths place (the "9" in "9.9").

Here, 9 > 1.
→ At this point, 9.9 is already larger than 9.11.

We don’t even need to look at the hundredths place (the second decimal digit) because the tenths place decides the comparison.

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3. (For completeness) Check the hundredths place:

• 9.11 has 1 in the hundredths place.
• 9.9 can be written as 9.90 (adding a trailing zero doesn’t change its value).
  • Hundredths digit: 0

1 > 0, but this only matters if the tenths digits were equal. Since they aren’t (9 > 1), this step is unnecessary for the final answer.

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Visual Comparison

Number	Whole Part	Tenths	Hundredths
9.11	9	1	1
9.9	9	9	0 (implied)

Since 9 (tenths) > 1 (tenths), 9.9 > 9.11.

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Common Mistake to Avoid

• Don’t compare the decimal digits as whole numbers (e.g., thinking “11 > 9” because 11 is larger than 9).
  Decimals rely on place value, not the number of digits.
  • 9.9 = 9 + 0.9
  • 9.11 = 9 + 0.11
    Since 0.9 > 0.11, 9.9 > 9.11.

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Final Answer

No, 9.11 is not greater than 9.9.
9.9 is greater than 9.11. ✅