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# Express the following numbers in usual form.

(i) 3.02×10^{−6 }(ii) 4.5×10^{4 }(iii) 3×10^{−8 }(iv) 1.0001×10^{9}

(v) 5.8×10^{12 }(vi) 3.61492×10^{6 }

**Solution:**

Standard form of exponents is used to represent a very small or large number following a certain set of rules.

The given set of numbers are in standard form. Let's convert them to their usual form as shown below.

(i) 3.02 ×10^{−6}

To convert a smaller number(negative powers of 10) to its usual form shift the decimal towards the left by the number of places equivalent to the power of 10.

3.02 × 10^{−6 }= 3.02/1000000

∴ its usual form is 0.00000302

(ii) 4.5 × 10^{4}

To convert a big number(positive powers of 10) to its usual form we need to move the decimal to its right by the number of places equivalent to the power of 10.

4.5 × 10^{4} = 45000

Thus, the usual form is 45000

(iii) 3 × 10^{−8} = 0.00000003 [Moving the decimal towards the left by 8 places]

(iv) 1.0001 × 10^{9 }= 1000100000 [Moving the decimal towards the right by 9 places]

(v) 5.8 × 10^{12 }= 5800000000000 [Moving the decimal towards the right by 12 places]

(vi) 3.61492 × 10^{6 }= 3614920 [Moving the decimal towards the right by 6 places]

**☛ Check: **NCERT Solutions for Class 8 Maths Chapter 12

**Video Solution:**

## Express the following numbers in usual form. (i) 3.02×10⁻⁶^{ }(ii) 4.5×10⁴^{ }(iii) 3×10⁻⁸^{ }(iv) 1.0001×10⁹^{ }(v) 5.8×10¹²^{ }(vi) 3.61492×10⁶

Class 8 Maths NCERT Solutions Chapter 12 Exercise 12.2 Question 2

**Summary:**

The following numbers in usual form (i) 3.02×10^{−6 }(ii) 4.5×10^{4 }(iii) 3×10^{−8 }(iv) 1.0001×10^{9 }(v) 5.8×10^{12 }(vi) 3.61492×10^{6 } are (i) 0.00000302 (ii) 45000 (iii) 0.00000003 (iv) 1000100000 (v) 5800000000000 and (vi) 3614920 respectively.

**☛ Related Questions:**

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