Decimals (Concepts & Computation) Nov. 30

Number Sense Whole number; number of people attending an event (305) Decimal; number of gallons of gasoline (3.65) Ratio; number of men compared to number of women (2:5) Fraction; measurement of diameter (¾) Percent; discount rate, interest rate (14.5%)

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

Exercise In what place is the underlined digit? 4.068 64.183 4.106 5.832 5.134 What number does the underlined name? 5.839 24.935 328.407 840.019 247.893 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

Thousandths 2 1 6 4. 5 7 8 2; thousands 1; hundreds 6; tens 4; ones 2 1 6 4. 5 7 8 2; thousands 1; hundreds 6; tens 4; ones 5; tenths 7; hundredths 8; thousandths

Exercise Write the decimals. ------ 4 ----- 86 ----- --- 2 ----- 609 89 3 5 125 ------ 4 ----- 86 ----- --- 2 ----- 1000 1000 1000 10 1000 Fifty-two thousandths Four and four thousandths Eight thousandths One hundred fifty-nine and twelve hundredths

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)

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

Changing Fraction to Decimal You can change a fraction to a decimal by dividing the numerator by the denominator Numerator; the top part of a fraction Denominator; the bottom part of a fraction When you divide until the remainder is zero, the decimal is a terminating decimal

Exercise Change each fraction to a decimal. 18 3 9 7 9 --- --- --- --- --- 25 40 8 32 20 Write each decimal as a mixed number or fraction in simplest form 0.65 0.225 0.006 1.4 0.625