Decimals By Mrs Degollado Making the foldable Follow
Decimals By Mrs. Degollado
Making the foldable Follow the instructions carefully. 1. Fold the sheet horizontally (landscape) in thirds. 2. The left side should be on top of the right side. Pg. 1 on the picture.
Place Value Chart D 100 s 1 hundreds E 10 s 2 tens C 1 s 3 ones I . M 10 ths 4 tenths A 100 ths 5 hundredths L 1, 000 ths 6 thousandths S 10, 000 th s 7 ten-thousandths
Rounding Decimals 1. Find the rounding digit. 2. Look at the number to the right of the rounding digit. Is it 5 or more? No Yes Remove all the numbers to the right of the rounding digit. Add 1 to the rounding digit and remove all the numbers after the rounding digit.
Examples: Rounding Decimals n Ex 1: Round 23. 5289 to the nearest tenths. 23. 5289 (step 1) 23. 5289 Answer: (step 2) 23. 5 Ex 2: Round 14. 986 to the nearest hundredths. 14. 986 (step 1) 14. 986 Answer: (step 2) 14. 99
Compare and Order Decimals 1. Be sure to align the digits so that all decimal points are in a vertical line. 2. Add zeros before the first digit or after the last digit if needed. 3. Compare each number on the corresponding place value from left to right. Hint: You could make a table as shown below to align the numbers and decimal point. 0 2 . 2 3 0 1 2 . 4 0 0 . 5 3 7 0 1 . 6 9 0
Example: Comparing & Ordering Decimals Arrange the following numbers in descending order. Ex. 1: 2. 23, 12. 4, . 537, 1. 69 Arrange the following numbers in ascending order. Ex. 2: 0. 65, 3. 25, 45. 7, 2. 123 . . . .
Adding and Subtracting Decimals n Be sure to align the terms so that all decimal points are in a vertical line. n Add or subtract numbers. Ex 1: 23. 568 + 235. 16= Ex 2: 652. 89 – 23. 456=
Multiplying Decimals n Pretend that there are no decimal points and multiply. n Count the number of decimal places to the right of the decimal points on both numbers. n Count the same amount of digits from right to left on the product. n Place the decimal point.
Examples: Multiplying Decimals Ex. 1) 2. 32 × 3. 1 Ex. 2) 2. 531(0. 21)
Dividing Decimals 1. Make the divisor a whole number by moving the decimal point all the way to the right. (Note: If there is no decimal point on the divisor then no movement is needed) 2. Count the same number of digits on the dividend starting from the decimal to the right. (Note: If there is no decimal point on the dividend, then add a decimal point after the last digit and move it the amount of digits needed by adding zeros to the right. ) 3. Place the decimal point on the dividend and then move it up directly on the quotient divisor
Examples: Dividing Decimals Ex. 1: 7. 392 ÷ 0. 48 = Ex. 2: 72 ÷ 0. 2 =
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