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JSS2: MATHEMATICS - 1ST TERM

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  1. Properties of Whole Numbers I | Week 1
    4Topics
    |
    2 Quizzes
  2. Properties of Whole Numbers II | Week 2
    4Topics
    |
    2 Quizzes
  3. Properties of Whole Numbers III | Week 3
    4Topics
    |
    1 Quiz
  4. Indices | Week 4
    2Topics
    |
    1 Quiz
  5. Laws of Indices | Week 5
    5Topics
    |
    1 Quiz
  6. Whole Numbers & Decimal Numbers | Week 6
    4Topics
    |
    1 Quiz
  7. Standard Form | Week 7
    3Topics
    |
    1 Quiz
  8. Significant Figures (S.F) | Week 8
    4Topics
    |
    1 Quiz
  9. Fractions, Ratios, Proportions & Percentages I | Week 9
    6Topics
    |
    1 Quiz
  10. Fractions, Ratios, Proportions & Percentages II | Week 10
    4Topics
    |
    1 Quiz
  11. Fractions, Ratios, Proportions & Percentages III | Week 11
    3Topics
    |
    1 Quiz
  12. Approximation & Estimation | Week 12
    1Topic
    |
    1 Quiz
Lesson Progress
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Example 1

Given that x = 85 000, and y = 25 000 find the value of

a. \( \scriptsize x \: + \: y \)

b. \( \scriptsize x \: \times \: y \)

c. \( \scriptsize x \: \div \: y \)

Give your answer in standard form.

Solution

a. x  + y    =   85 000  +  25 000

                     =   170 000

                     =  1.7 x 105

b. x x  y   =   85 000  x  25 000

                  =  8.5 x 104   x  2.5 x 104

                  = 8.5 x 2.5 x 104 x 104

                  = 21. 25 x 104 x 104

                  = 21.25 x 104+4

                 = 21. 25 x 108

                 = But 21.25 = 2.125 x 101

                  = (2.125 x 101) x 108

                  = 2.125 x 101+8

                  = 2.125 x 109

 c. x ÷ y   = \( \frac{x}{y} \\= \frac{85\not{0}\not{0}\not{0}}{25 \not{0}\not{0}\not{0}} \\= \frac{85}{25} \\= \frac{17}{5} \\ = \scriptsize 3.4 \\ = \scriptsize 3.4 \: \times \: 10^0\)  

Example 2

The population of Nigeria is about 145 million and the population of Britain is about 58 million. Write these numbers in standard form and find the difference in population between the two countries.

Solution

Nigeria = 145 million

= 145 x 1 000 000

= 145  x 106

but 145 = 1.45 x 102

Therefore,

= (1.45 x 102) x 106

= 1.45 x 102+6

= 1.45 x 108

Britain = 58  million

= 58 x 1 000 000

= 58 x 106

but 58 = 5.8 x 101

Therefore,

= (5.8 x 101) x 106

= 5.8 x 101+6   

=  5.8 x 107

Difference in population  =  145 million  – 58 million 

= 87 million

= 87 x 1 000 000

= 87 x 106

but 87 = 87 x 101

Therefore,

= (8.7 x 101) x 106 

= 8.7 x 101+6

= 8.7 x 107

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