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How many sig figs are there?. 1. The leftmost nonzero digit is the most significant digit 2. If there is no decimal point, the rightmost nonzero digit is the least significant digit 3. If there is a decimal point, the rightmost digit is the least significant digit even if it is a zero.
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How many sig figs are there? 1. The leftmost nonzero digit is the most significant digit 2. If there is no decimal point, the rightmost nonzero digit is the least significant digit 3. If there is a decimal point, the rightmost digit is the least significant digit even if it is a zero. 4. All digits between the least and most are also significant. TOC
Examples 3010 3010.00 20 20. 20.0 30.010 3.200 x 104 TOC 3, 6, 1, 2, 3, 5, 4
Examples 100 1.0 x 102 100. .012 .000150 37 people in a class 50,000 at a rally TOC 1, 2, 3, 2, 3, n/a, ??
How many sig figs in 1250 ? W 3
How many sig figs in 300 ? W 1
How many sig figs in 300. ? W 3
How many sig figs in 3.0 x 102 ? W 2
How many sig figs in 2.10 ? W 3
How many sig figs in 31.00150 ? W 7
How many sig figs in .0232 ? W 3
How many sig figs in .00150 ? W 3
How many sig figs in 8.900 x 105 ? W 4
Rule for multiplication and division Round final answer to least number of sig figs of the operands: 123.50 x 21 2593.5 round to 2 places: 2600 Never round until totally done. TOC
Whiteboards x and / answer rounding TOC
Express the answer with the correct number of sig figs: 1329.0 x 25 = ? = 33,225 -> 33,000 W 33,225 > 33,000
Express the answer with the correct number of sig figs: 102.085 / 323 = ? = 0.316052632 -> .316 W 0.316052632 >.316
Express the answer with the correct number of sig figs: 8.015 / 570 = ? = 0.014061404 -> .014 W 0.014061404 > .014
Rule for addition and subtraction Round final answer to least commonplace: 123.5497 +21.1 144.6497 -> 144.6 as an expressed answer Again, never round until totally done. <IB apparently does not require this rule> TOC
Whiteboards + and - answer rounding TOC
Express the answer with the correct number of sig figs: 1.058 + 15.1 = ? = 16.158 -> 16.2 W 16.158 = 16.2
Express the answer with the correct number of sig figs: 98 + 12 = ? = 110 -> 110. W 110 > 110.
Express the answer with the correct number of sig figs: 27.52 - 3 = ? 24.52 -> 25 W 24.52 > 25
Express the answer with the correct number of sig figs: 100 + 16 = ? = 116 - > 100 Quit your whining - use 116 W 100