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Challenge Time!

What numbers are missing?

Goal:

Goal:

Mystery box isometric icon. Clipart image isolated on white background.

Oh no! Some of the numbers from the problem below are missing. Click through the slides to see an example of how to solve a mystery numbers problem.

Slide: 1 / 3

Consider the problem...

Four hundred twenty didvided by (?) minus 30 equalsone hundred twenty minus one hundred twenty equals zero; the quotient is twenty (?).

Remember that multiplication is the opposite of division. Sometimes working backwards with multiplication is helpful when solving a division mystery.

Use your understanding of multi-digit division equations to solve the activity below by determining the missing digits. When ready, click each tab to reveal the solution.

Eight hundred (?) five divided by forty (?); the quotient is nineteen.

The missing numbers are both 5. If you focus on the numbers that you have, guess and check along with the clues the numbers give you, you will be able to solve for what you don’t know.

You can see that your quotient is 19.

You can also see that you are making 19 groups with 40-something in them (the 4 in tens place of the divisor gives you this clue).

You can see that your dividend has an 8 in the hundreds place and a 5 in the ones.

Using multiplication, you can guess and check to find a factor to multiply 19 with that gives a product of 8 _ 5. The only factor that fits is 45.

Eight hundred fifty five divided by forty five minus forty five equals four hundred five minus four hundred five equals zero; the quotient is nineteen.
Forty five times nineteen equals four hundred five plus four hundred fifty; the sum equals eight hundred fifty five.

Click the image below.

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Mystery box clip art. Text bubble: Congratulations, you have solved the case!