an estimate is an approximation of a number based on reasonable assumptions. not the same as...
TRANSCRIPT
MATHEMATICS AND SCIENCE
Estimate
An estimate is an approximation of a number based on reasonable assumptions.
Not the same as guessing!!!Based on known info
Scientist must sometimes rely on estimates when they cannot obtain exact numbers
Accuracy and Precision
Accuracy – refers to how close a measurement is to the true value.
Precision – refers to how close a group of measurements are to each other.
Neither Accurate or Precise
Accurate and
Precise
Precise but not
Accurate
Significant Figures
The significant figures in a measurement include all the digits that have been measured exactly, plus one whose value has been estimated.
Several ways to determine the average number.1. Mean - is the numerical average by adding up
all the numbers and then dividing by the total number of items in the list.
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Mean
Test scores: Mean =
88947290
Several ways to determine the average number.2. Median – the middle number in a set of
data.- Place all the numbers in order from
smallest to largest. Circle the middle number.
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Median
110 102 110 107 94 110 109
Median =
Several ways to determine the average number.
2. Mode – the number that appears most often in a list of numbers.
- Place all the numbers in order from smallest to largest.
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Mode
110 102 110 107 94 110 109
Mode =
Percent Error
Percent error is used to determine how accurate, or close to the true value an experimental value really is.
Graphing A graph is a useful tool that may help
scientist interpret data by revealing unexpected patterns.
Line graph – shows how the responding or dependent variable changes in response to the manipulated or independent variable. The horizontal axis – runs left to right. The vertical axis – runs up and down. Includes a line of best fit – this shows the
overall trend of data. If a graph shows no identifiable trend then there
is no relationship between the variables
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A line of best fit emphasizes the overall trend shown by all the data taken as a whole.
Trend LinesLinear Trends – A line graph in which the points fall on a straight line
Nonlinear Trends – Points don’t fall on the line
No Trend – Points are scattered
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Safety in the Science Lab
• Good preparation helps you stay safe when doing science activities in the lab.
• Just as in the lab, good preparation helps you stay safe when doing science activities in the field
• When an accident occurs, no matter how minor, notify your teacher immediately. Then, listen to your teacher’s directions and carry them out quickly.