Page 123 - Knowledge Organiser Yr9 24-25

Knowledge Base: Science Working scientifically Year 9
10. Using equations
Solving equations using:
Worked examples:
12. Additional math for science skills
12.1 What is the mode? The number in a data set that appears the most (most frequent).
12.3 What is the mode? 1.7
12.2
What is the median?
Place the numbers from the data set in order of size. The number in the middle is the median.
Here is a data set:
12.4
What is the median?
- Place numbers in size order: 1.2 1.3 1.4 1.6 1.7 1.7 - There are 2 numbers in the middle: 1.4 and 1.6. Add the middle values together and divide by 2
- 1.4 + 1.6 = 3.0- 3.0 ÷ 2 = 1.5
12.5
Round the following numbers to 2 significant figures (s.f) a) 3527
b) 3.179
c) 0.007847 d) 7093
a) 3530
b) 3.18
c) 0.00785
d) 709
Remember: If a number starts with zeros, these do not count as as
significant figures. Ex: 0.00627 only has 3 significant figures.
If a zero is in-between two numbers, it is significant. Ex: 802 has 3 s.f.
12.6
Round these numbers to 2 decimal places: a) 0.156
b) 56.847
c) 1.0052
a) 0.16 b) 56.85 c) 1.01
12.6
Put the following numbers into standard form:
a) 0.00001
b) 134000
c) 0.00000026
a) 1.0 x 10-5 b) 1.34 x 105 c) 2.6 x 10-7
12.8
Convert these numbers out of standard form: a) 1.2 x 10-3
b) 5.0 x 106
c) 8.0 x 10-4
a) 0.0012
b) 5 000 000 c) 0.0008
11. Prefixes & converting between
11
Convert the following units:
a) 12kW into W
b) 1.5mm into nm c) 42 000 kJ into GJ d) 5800 mA into A
a) 12 x 1000 = 12 000 W
b) 1.5 x 1000 x 1000 = 1 500 000 nm c) 42 000 ÷ 1000 ÷ 1000 = 0.042 GJ d) 5800 ÷ 1000 = 5.8 A
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