Writing Numbers with Decimals

Writing Decimals : 

Writing Decimals When you write decimals you use the same words as you use to write whole numbers. There are two specific differences and musts to writing decimals: 1. add “-ths” to the end of each place value name: tenths ten-thousandths hundredths hundred-thousandths thousandths millionths 2. use the word “and” between the last whole number and the decimal name Example: 3.21 = three and twenty-one hundredths

Rounding Decimals : 

Rounding Decimals To round decimals you follow the same rules as you do to round whole numbers. Look at the digit you wish to round, decide if the number to it’s right will cause it to round up or remain the same Example: Round to the nearest tenth 3.912 = 3.9 ↓ Look at the 9, decide if the 1 to it’s right will make it round up or remain the same In this case, the 1 indicates to leave the 9 alone

Comparing & Ordering Decimals : 

Comparing & Ordering Decimals You will compare & order decimals as you compare whole numbers as well. Line the decimals up when you write the numbers vertically to maintain the correct number. You can add 0’s to a decimal to help hold place value and for easier comparison. They are highlighted them in red below. Example: 12.98, 0.912, 81.099, 4.56 = 0.912, 4.560, 12.980, 81.099 12.980 0.912 81.099 4.560

Practice – Writing & Comparing Decimals : 

Practice – Writing & Comparing Decimals Write the following decimals in words. 15.23 0.8 5.982 102.61 74.538 (Answers are after the next slide in red) Compare the following decimals. Put them in order from least to greatest. 14.512, 14.251, 15.23, 5.241, 8.56

Practice – Rounding Decimals : 

Practice – Rounding Decimals Round these decimals to the nearest place indicated. Tenths Hundredths Whole Number 14.652 14.652 14.652 0.985 0.985 0.985 2.431 2.431 2.431

Practice – Answers : 

Practice – Answers Writing decimals - 1. 15.23 – fifteen and twenty-three hundredths 0.8 – eight tenths 5.982 – five and nine hundred eighty-two thousandths 102.61 – one hundred two and sixty-one hundredths 74.538 – seventy-four and five hundred thirty-eight thousandths Comparing decimals. Order from least to greatest. 14.512 14.251 15.230 5.241 8.560 5.241, 8.56, 14.251, 14.512, 15.23

Practice – Answers : 

Practice – Answers Round these decimals to the nearest place indicated. Tenths Hundredths Whole Number 14.652 14.652 14.652 0.985 0.985 0.985 2.431 2.431 2.431 Tenths Hundredths Whole Number 14.7 14.65 15 1.00 1.00 1 2.4 2.43 2