High School

A: Reasoning with Decimal Fractions

Mystery number has the following clues:
1. It is more than 6.25 but less than 6.35.
2. Its hundredths digit is 8.
3. Its tenths digit is an even number.
4. The sum of its digits is 16.

What is the number? Show how you worked it out.

Answer :

To solve the problem, let's analyze each clue step by step:

  1. More than 6.25 but less than 6.35:

    This means the number can be 6.26, 6.27, 6.28, 6.29, 6.30, 6.31, 6.32, 6.33, or 6.34.

  2. Hundredths digit is 8:

    From the numbers listed above, we're looking for numbers where the digit after the decimal and in the hundredths place is 8. This narrows it down to: 6.28.

  3. Tenths digit is an even number:

    In the number 6.28, the tenths digit (2) is even, so 6.28 fits this clue.

  4. Sum of its digits is 16:

    Finally, let's add the digits in 6.28: 6 + 2 + 8 = 16. This matches the clue.

After evaluating all the conditions, the mystery number is 6.28.