Home > Grade 5 > Multiplying Decimals to Make a Whole Number Product

Multiplying Decimals to Make a Whole Number Product

Directions: Using the digits 1 to 9 at most one time each, fill in the boxes to make a whole number product.

Hint

Hint

How can we tell if it is even possible to make a whole number product?
What digits would be better or worse choices for making a whole number product?

Answer

Answer

There are many answers. For example:
9.6 x 8.75 = 84
9.6 x 1.25 = 12
1.6 x 3.75 = 6
4.8 x 3.75 = 18
4.8 x 6.25 = 30
4.8 x 1.25 = 6
6.4 x 1.25 = 8
Note what they all have in common!

Source: Owen Kaplinsky

Print Friendly, PDF & Email

Check Also

Adding Three Fractions

Directions: Using each of the digits from 0-9 only once, fill in the boxes to …

12 comments

  1. another one… 9.6 x 1.25 = 12

  2. Thanks! I’ll add it to the answer key.

  3. Hi
    If you think about multiplying integers, you need the product to have a factor of 1000. I.e. you need prime factors of the multipliers to include 5^3 and 2^3. Additionally, the factors of 5 and 2 must stay in separate multipliers otherwise one would have to end in zero which is not allowed.
    So possible numbers that would work are:
    1.6,2.4,3.2,4.8,5.6,6.4,7.2,9.6
    multiplied by
    1.25,3.75,6.25,8.75
    Any combination of these will work, if the digits are unique.

  4. 3.75 X 4.8 =18 Also Works

  5. Please update answer – I thought there was only one solution then looked in the comments.

  6. 6.25 x 4.8 = 30

  7. I got an answer of 1.25 x 4.8 = 6

  8. 6.4 times 1.25 is another answer to get 8… from one of my amazing 5th grade students!

  9. The answers have been updated. Thank you for your posts.

  10. I see you don’t monetize openmiddle.com, don’t waste your traffic, you
    can earn additional cash every month with new monetization method.
    This is the best adsense alternative for any type of website (they approve all websites), for more details simply
    search in gooogle: murgrabia’s tools

Leave a Reply

Your email address will not be published. Required fields are marked *