Lesson Objective Revise how to write numbers using Standard Form Understand what the notation for Standard Form Means Begin to use a calculator to solve problems involving Standard Form
Match the items with their correct sizes. Can you write each size in Standard Form?
A number written in Standard Form will always look like this: Number here MUST be: 1 a < 10 Must always be written as × 10n n is +ve for big numbers n is –ve for small numbers
Important key facts about Standard Index Form Write the number in the following form: a × 10n Number here MUST be: 1 ≤ a < 10 Must always be written as × 10n n is +ve for big numbers n is –ve for small numbers Eg 6.23 × 105 = 623000 4.21 × 10-3 = 0.00421
Write these numbers in Standard Index Form: 1. Write these numbers in Standard Index Form: 40 000 b) 120 000 c) 623 000 000 0.000 05 e) 0.000 034 f) 6.2 g) 600 040 000 h) 0.256 i) 1.003 2. (a) Which planet has the largest diameter? (1) (b) Which planet has the smallest diameter? (c) Which planet has a diameter approximately 10 times that of Venus? (d) Write 4.88 × 106 as an ordinary number. (e) What is the diameter of Pluto in kilometres? Give your answer in standard form. (2)
Using your calculator to solve problems Involving SI Form Compare these two problems A car travels 600 m in 84 seconds. What is its average speed during the journey? 2) A particle travels 5 × 108 m in 3 × 103 seconds what is the average speed of the particle during the journey?
Lesson Objective Revise how to write numbers using Standard Form Understand what the notation for Standard Form Means Be able to do arithmetic without a calculator using Standard Form
Write this number in Standard Index form: 6 000 000
Write this number in Standard Index form: 72 000 000 000
Write this number in Standard Index form: 0.067
Write this number in Standard Index form: 0.000 000 032
Write this number in Standard Index form: 0.5
Write this number in Standard Index form: 10
Write this number in Standard Index form: 8
Write this number as a Decimal: 5.2 × 106
Find (without a calculator): If a = 3 × 105 and b = 2 × 103 Write down the value of a × b in Standard Form
Find (without a calculator): If a = 3 × 104 and b = 4 × 102 Write down the value of a × b in Standard Form
Find (without a calculator): If a = 6 × 103 and b = 3 × 104 Write down the value of a × b in Standard Form
Find (without a calculator): If a = 6 × 103 and b = 3 × 104 Write down the value of a + b in Standard Form
Find (without a calculator): If a = 6 × 105 and b = 8 × 105 Write down the value of a + b in Standard Form
Find (without a calculator): If a = 2.4 × 105 and b = 3 × 104 Write down the value of a + b in Standard Form
Find (without a calculator): If a = 9 × 105 and b = 3 × 104 Write down the value of a ÷ b in Standard Form
Find (without a calculator): If a = 12 × 108 and b = 4 × 105 Write down the value of a ÷ b in Standard Form
Find (without a calculator): If a = 4 × 108 and b = 8 × 106 Write down the value of a ÷ b in Standard Form
Important key facts about Standard Index Form Write the number in the following form: a × 10n Number here MUST be: 1 ≤ a < 10 Must always be written as × 10n n is +ve for big numbers n is –ve for small numbers Eg 6.23 × 105 = 623000 4.21 × 10-3 = 0.00421
For S.I. Form without a calculator: When multiplying and dividing use the normal index laws, but make certain the final answer is properly in S.I. Form Eg. 7×104 × 3×105 = 21×109 = 2.1×1010 When adding and subtracting take the numbers out of S.I. Form (or at least adjust them so that the index is the same) then add/subtract as normal Eg. 7×103 + 3×105 = 7×103 + 300×103 = 307×103 = 3.07×105 (or do 7000 + 300000 = 307000 = 3.07 ×105)
Let a = 3 × 106 b = 2 × 10-4 c = 5 × 107 d = 8 × 106 Find: a × b c2 a × c d ÷ b b ÷ d a + d a + c a - c
Pick two different numbers and an operation. 1.5×101 3.6×1015 3.6×103 2.5×10-8 2×10-11 6×1013 2.4×106 1.6×101 Pick two different numbers and an operation. You capture the square if your calculation is correct. 1.22×108 9.008×10-3 2.5×1011 1.2×1013 2.7×105 2.4×102 3×10-10 6×101 2.5×108 2.4×1014 5×1010 4.8×1013 8×1011 3×102 3.2×100 Operation: + × ÷ 3.04×107 3.2×107 Numbers: 4×105 3×107 2×106 1.2×108 8×10-6 9×10-3
Q2. For each calculation circle the answer that is correct and is in standard form. (a) (3 × 105) × (4 × 107) Answers 12 × 1012 1.2 × 1036 12 × 1035 1.2 × 1013 (b) (4 × 10–8) ÷ (8 × 10–2) Answer 0.5 × 10–6 5 × 104 5 × 10–7 5 × 10–5 (Total 2 marks)