Question

It is an odd number. it is greater than 142. it is less than 156. rounded to the nearest ten, the rounded value is less than the mystery number. rounded to the nearest hundred, the rounded value is greater than the mystery number.

Answer 1

The odd numbers between 142 and 156 are these:

143, 145, 147, 149, 151, 153, and 155.

Of these, 143 to the nearest ten is 140.

Likewise, 151 to the nearest ten is 150.

And, 153 to the nearest ten is 150.

Of the seven original numbers, 143, 151, and 153 round to a nearest ten that
is less than the possible mystery number.

To the nearest hundred, 143 goes to 100; 151 goes to 200, and 153 goes to 200.

Of those three, only two round to a nearest hundred that is bigger than the mystery number.

Answer: 151 and 153 are the mystery numbers.

Answer 2

So, the mystery number could be 151 or 153.

Explanation:

To solve, use the first three clues to make a list of possible mystery numbers. The mystery number is an odd number that is greater than 142 and less than 156, so the list of possible mystery numbers, so far, is shown below.

The fourth clue says that, when the mystery number is rounded to the nearest ten, the rounded value is less than the mystery number. Any numbers that round down to the nearest ten could be the mystery number. In order to round down, the ones digit must be less than 5, so remove any numbers with a ones digit that is 5 or greater.

The last clue says that, when the mystery number is rounded to the nearest hundred, the rounded value is greater than the mystery number. Any numbers that round up to the nearest hundred could be the mystery number. In order to round up, the tens digit must be 5 or greater, so remove any numbers with a tens digit that is less than 5.

Have a good day :)