This document provides an introduction to decimals, including: - Decimals represent numbers with fractional parts using powers of ten as denominators. The decimal point separates whole numbers from fractional parts. - The value of each digit in a decimal is determined by its place value - to the left of the decimal point for whole numbers, and to the right for fractional parts. - Decimals can be compared by examining the value of each place moving from left to right. They can also be ordered from least to greatest.

1. Decimals

2. Where have you seen decimals? Money

3. Where have you seen decimals? Sports Statistics

4. Where have you seen decimals? Measurements

5. What words contain the prefix dec-? decade decimeter decimal

6. What does dec- mean?

7. What are decimals ? Decimals are numbers that include fractional parts using denominators that are powers of ten.

8. What is a decimal point ? A decimal point is to the right of the ones place. 1.0

9. Where is the tenths place ? 0.1 The tenths place is to the right of the decimal point.

10. Where is the hundredths place ? The hundredths place is to the right of the tenths place. 0.01

11. Decimal Place Value Chart 0.01 ones tenths hundredths

12. 1.0 1 whole

13. 0.1 one tenth 1/10

14. 0.01 one hundredth 1/100

15. Decimals and Place Value A decimal is a number with a decimal point in it (6.52, 0.5, 0.01) The value of digits in a decimal is based on the number 10 The digits to the left of the decimal point represent whole number The numbers to the right of the decimal point represent some part of 1

16. Exercise In what place is the underlined digit? 4.0 6 8 6 4.183 4.10 6 5 .832 5.1 3 4 What number does the underlined name? 5.8 3 9 24. 9 35 3 2 8.407 840.01 9 247.89 3 Circle the number in which the 3 has the greater value. 73.249 856.634 1,420.038 52.243 78.329 865.463 1,240.308 49.321

17. Comparing and Ordering Decimals Compare the decimals 0.27 and 0.25 Compare number of ones (0 = 0) Compare number of tenths (2 = 2) Compare number of hundredths (7 > 5)

18. Exercise Write <, =, or >. 0.45 0.045 0.25 0.250 0.31 0.310 0.9 0.09 0.07 0.70 0.6 0.600 0.66 0.6 0.503 0.53 0.129 0.12 Write in order from the least to the greatest 4.4 ; 4.7 ; 4.38 0.63 ; 0.6 ; 0.3 5.01 ; 4.98 ; 5 17.182 ; 1.728 ; 17.218

19. Decimals are read as : 345.674 - Three hundred forty five point six seven four 23.601 - Twenty three point six zero one 9.108 - Nine point one zero eight

20. Exercise Read the decimals aloud 208.015 1298.652 3.51 21.968 v

21. 2.645 X 3.2 5290 See an example 2.645 X 3.2 Multiply 2645 by 2 Multiply 2645 by 3 Add them Product