What makes 10 - A book about number facts

Ten is a special numberWhat makes ten?Finding facts of tenGlossary

Marcia S Freeman

A Book About Number Facts

© 2008 Rourke Publishing LLC

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PHOTO CREDITS: title page © Nancy Catherine; pg.5 © Dan Bayley; pg.6 © Mike Morley; pg.11 © Christine Glade; pg.12 © YinYang; pg.13 © Mark Yuill; pg.14 © Ian Peters; pg.15 © Eric Lsselee; pg.17 © Mecaleha; pg.22 © Paul Kline

Editor: Robert Stengard-Olliges

Cover design by Nicola Stratford, bdpublishing.com

Library of Congress Cataloging-in-Publication Data

Freeman, Marcia S (Marcia Sheehan),

1937-What makes ten? : number facts / Marcia S Freeman.

p cm (Math focal points)

Table of Contents

A long time ago, people found their fingerswere useful in counting Count your fingers.

Do you see why ten is an important number?

Ten Is a Special Number

We use ten different symbols to write

numbers The symbols are 0, 1, 2, 3, 4, 5, 6, 7,

8, and 9 But there is no separate symbol

We write the number ten with a one in the

ten’s place and a zero in the one’s place.

Ten is important in our money system, too

Ten pennies make a dime Ten dimes make

a dollar

= 10¢

10¢ 10¢ 10¢ 10¢ 10¢

10¢ 10¢ 10¢ 10¢ 10¢

=$1.00

Count your fingers How many ways can youmake ten?

You can add one and nine to make ten Wewrite: 1 + 9 = 10

What Makes Ten?

1 9 10

+

Two and eight makes ten

2

8

10

+

What do you need to add to three to make

ten? 3 + 7 = 10

3 7

10

+

Four and six is another pair that adds up to

4

6

10

+

Five plus five is easy You can probably count

by fives 5, 10, 15, 20, 25, 30

5 5 10

+

The last pair to make ten is ten and zero

10 + 0 = 10

10 0 10

+

One way to start adding columns of numbers

is to spot the pairs of numbers that add up toten Here is how it’s done:

Finding Facts of Ten

35 16 24

+

Problem: Step 1: 35

16 24

5 10

+

Step 2:

Step 3:

Step 4:

35 16 24

5

10 15

35 16 24

42 28 17 3

+

Problem: Step 1:

42 28 17 3

10 10

+

Step 2:

42 28 17 3

10 10

Let's try another problem

Step 3:

42 28 17 3

10 10

Step 4:

42 28 17 3 90

To be a good mathematician, you need to

know all the addition facts Start with the

numbers that make ten, and then tackle theharder ones like 12 + 3

About the Author

Marcia S Freeman loves writing Her fifty or more children’s books include science, geography, and math A Cornell University graduate, she has taught science and writing to children and their teachers