Chapter 2, Problem 2.105AQAP

Interpretation Introduction

(a)

Interpretation:

The value 0.00001258 L needs to be round off up to three significant figures.

Concept Introduction:

The following rules needs to be followed to determine the correct number of significant figures in a given number:

1. All non-zero digits are significant.
2. Trailing zeros after decimal are significant.
3. All zeros in between two non-zero or significant figures are significant.

Rules for rounding off numbers are as follows:

1. If the digit to be rounded off is followed by digit greater than 5, the number will be rounded up.

For example: Rounding off number 38, the first digit is followed by digit 8 which is greater than 5 thus; the number will be rounded up to the nearest ten that is 40.

2. If the digit to be rounded off is followed by digit zero or less than 5, the number will be rounded down.

For example: Rounding off number 33, the first digit is followed by digit 3 which is less than 5 thus; the number will be rounded down to the nearest ten that is 30.

3. If the digit to be rounded off is followed by digit 5 and it is even, then it will remain the same, but if the digit is odd, it will be rounded up to get an even number.

Interpretation Introduction

(b)

Interpretation:

The value $3.528\times {10}^2\text{kg }$ needs to be round off up to three significant figures.

Concept Introduction:

The following rules needs to be followed to determine the number of significant figures:

1. All non-zero digits are significant.
2. Trailing zeros after decimal are significant.
3. All zeros in between two non-zero or significant figures are significant.

Rules for rounding off numbers are as follows:

1. If the digit to be rounded off is followed by digit greater than 5, the number will be rounded up.

For example: Rounding off number 38, the first digit is followed by digit 8 which is greater than 5 thus; the number will be rounded up to the nearest ten that is 40.

2. If the digit to be rounded off is followed by digit zero or less than 5, the number will be rounded down.

For example: Rounding off number 33, the first digit is followed by digit 3 which is less than 5 thus; the number will be rounded down to the nearest ten that is 30.

3. If the digit to be rounded off is followed by digit 5 and it is even, then it will remain the same, but if the digit is odd, it will be rounded up to get an even number.

Interpretation Introduction

(c)

Interpretation:

The value $125111\text{ m}$ needs to be round off up to three significant figures.

Concept Introduction:

The following rules needs to be followed to determine the number of significant figures:

1. All non-zero digits are significant.
2. Trailing zeros after decimal are significant.
3. All zeros in between two non-zero or significant figures are significant.

Rules for rounding off numbers are as follows:

1. If the digit to be rounded off is followed by digit greater than 5, the number will be rounded up.

For example: Rounding off number 38, the first digit is followed by digit 8 which is greater than 5 thus; the number will be rounded up to the nearest ten that is 40.

2. If the digit to be rounded off is followed by digit zero or less than 5, the number will be rounded down.

For example: Rounding off number 33, the first digit is followed by digit 3 which is less than 5 thus; the number will be rounded down to the nearest ten that is 30.

3. If the digit to be rounded off is followed by digit 5 and it is even, then it will remain the same, but if the digit is odd, it will be rounded up to get an even number.

Interpretation Introduction

(d)

Interpretation:

The value $34.9673\text{ s}$ needs to be round off up to three significant figures.

Concept Introduction:

The following rules needs to be followed to determine the number of significant figures:

1. All non-zero digits are significant.
2. Trailing zeros after decimal are significant.
3. All zeros in between two non-zero or significant figures are significant.

Rules for rounding off numbers are as follows:

1. If the digit to be rounded off is followed by digit greater than 5, the number will be rounded up.

For example: Rounding off number 38, the first digit is followed by digit 8 which is greater than 5 thus; the number will be rounded up to the nearest ten that is 40.

2. If the digit to be rounded off is followed by digit zero or less than 5, the number will be rounded down.

For example: Rounding off number 33, the first digit is followed by digit 3 which is less than 5 thus; the number will be rounded down to the nearest ten that is 30.

3. If the digit to be rounded off is followed by digit 5 and it is even, then it will remain the same, but if the digit is odd, it will be rounded up to get an even number.