Rounding big numbers

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Purpose:

To help your child learn to round numbers to the nearest 10, 100 or 1000.

What you need:

A set of playing cards. (Ace = 1, Jack = 0)

What to do:

Ask your child to take 4 cards and arrange them to make a number.

Ask your child:

  • How do you say that number?
  • Can you round it to the nearest 10? 7230
  • Can you round it to the nearest 100? 7200
  • Can you round it to the nearest 1000? 7000

Using the same cards, ask your child to make a number close to a number you choose.

For example: for the cards

Make a number close to 3000    2731

Make a number close to 4000    3712

What to expect your child to do:

To read the number correctly and to round it to the nearest 10, 100 and 1000.

Variations:

  • Use 5 cards to make numbers.
  • Two players could make numbers and to see who can make the biggest number.

He Kupu Māori:

round (a number) whakaawhiwhi (-a)
closest thousand te mano e pātata ana
five digit number tau mati-rima

He Whakawhitinga Kōrero:

  • Tangohia ētahi kāri e rima, ka hanga ai i tētahi tau mati-rima. (Take five cards and make a five digit number.)
  • Pānuihia mai tēnā tau? (Read that number.)
  • Whakaawhiwhia ki te 10 e pātata ana. (Round it to the nearest ten.)
  • Whakaawhiwhia ki te 100 e pātata ana. (Round it to the nearest hundred.)
  • Whakaawhiwhia ki te 1000 e pātata ana. (Round it to the nearest thousand.)
  • Hangaia tētahi tau e pātata ana ki te whā tekau mā ono mano. (Make a number close to 46000.)

Download a file of this activity:

PDF (172KB)