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Rounding Decimals and Fractions. NS4. Rounding. Sometimes you do not need to know an exact number. Knowing a number that is close to the actual number is good enough. Rounding is one way to find an approximate number. A number line can help us understand rounding!.
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Rounding • Sometimes you do not need to know an exact number. Knowing a number that is close to the actual number is good enough. • Rounding is one way to find an approximate number.
Round 7.6 to the nearest whole number. • Is it closer to 7 or 8? 7.5
Tenths Review • Which digit is in the tenths place in the number below? • The tenths place is always immediately behind the decimal point. 25.89
Round 23.61 to the nearest tenth. Which digit is in the tenths place? 23.61 Look at the digit directly to the right of the 6. 23.61 Does it tell us to round up (23.7) or not (23.6)? 23.6
Hundredths Review Which digit is in the hundredths place? The hundredths place is always two places behind the decimal point. 14.628
Now round 14.268 to the nearest hundredth. 14.628 Look at the digit behind the 2. Does it tell you to round up (14.63) or not (14.62)? 14.63
Rounding Fractions • Sometimes you need to round fractions to the nearest half. Milton measured a nail and recorded the length as inch. What is the length to the nearest ½ inch? 9 16
9 Rounding Fractions 16 What is the length to the nearest ½ inch? Use (or imagine) a number line. Where does the fraction go on the number line? Is it closer to 0, ½ or 1? ½ 0 1
3 Rounding Fractions 8 What is the length to the nearest ½ inch? Use (or imagine) a number line. Where does the fraction go on the number line? Is it closer to 0, ½ or 1? ½ 0 1
What is 6.702 rounded to the nearest hundredth? • 6.50 • 6.70 • 6.71 • 7.00
What is 5⅕ rounded to the nearest half? • 5¼ c. 6 • 5 ½ d. 5 (Imagine where it would go on the number line.) 6 5
A 10K race is about 6.21 miles. Which of the numbers below is rounded to the nearest tenth? • 6.22 • 6 • 6.2 • 6.1
Round 4⅞ to the nearest half. • 4 • 4½ • 5
Round 89.155 to the nearest hundredth. • 89 • 89.15 • 89.16 • 89.20
What is 16⅘ rounded to the nearest half? • 16 • 16½ • 17 • 16¾
What is ¾ rounded to the nearest whole number? • 0 • ½ • ¾ • 1
Round 17.25 to the nearest tenth. • 17.2 • 17 • 17.24 • 17.3
Time for a joke! Nan: Let’s play school. Dan: OK, let’s play I’m absent. The End!