Example Multiply 26.54 by 20.25

Solution : Step 1. Ordinary multiplication of 2654 and 2025 = 5374350

Step 2. Insert the decimal point so that we have as many decimal places as is the sum of decimal places in multiplicand and multiplier,

i.e. ( 2 + 2 = 4 decimal places ).

\ 26.54 ´ 20.25 = 537.4350

Example Multiply 0.7 ´ 0.7 ´ 0.7

Solution : 0.7 ´ 0.7 ´ 0.7 = 0.343

Example Multiply 0.5 ´ 0.05 ´ 0.0005

Solution : 0.5 ´ 0.05 ´ 0.0005 = 0.0000125

Ratio and Proportion

Ratio

1. The comparison of two quantities by division is called their ratio, i.e.stating the first quantity to be how many times of the second one or what multiple of the second number is the first number.

2. The two numbers stated above are known as the terms of that ratio.

3. The first number is called antecedent (numerator ) and the second number is Called consequent ( denominator ).

4. The two terms of the ratio must be of the same type with same units.

5. A ratio is a pure number. It has no unit.

6. A ratio is always in its simplest form which is obtained by canceling the common factors of the two terms.

7. The ratio between two quantities ‘a’ and ‘b’ is written as .... or
a : b

1) is called fractional ratio.

2) a : b is called a linear ratio

8. Of the two ratios

i) if

ii) if

iii) if

1. Equality of ratios is called proportionality.

2. If then a, b, c and d are in proportion, then a, b, c and d are called 1st, 2nd, 3rd and 4th proportional respectively.

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Index

Introduction
1.1 Pre-requisties
1.2 Common Mathematical Symbols
1.3 Some Properties of Basic Mathematical Operations
1.4 Real Numbers

Chapter 2