Page 80 - Start Up Mathematics_7

4. Two rational numbers having different numerators and different denominators can never be
equal.

5. The number 1 is an identity element for division of rational numbers.
6. There exists at least one integer between two distinct rational numbers.

7. The absolute value of numerator and denominator of a rational number in its simplest form
are coprime.
8. Every terminating decimal represents a rational number but every rational number is not
necessarily represented by a terminating decimal.

9. Every irrational number is represented by a non-terminating repeating decimal.
a c
10. For two rational numbers and where a, b, c and d are positive integers, we have another
b
d
a + c
rational number which always lie between them.
b + d
Fill in the Blanks
p
1. A rational number is said to be in _____________ form if p and q have no common factor
other than 1. q

2. There are _____________ rational numbers between any two rational numbers.

a c
3. Two fractions and are equal, iff, ad equals _____________.
b d
4. If a, b and c are integers and b > 0, then a < c iff a _______ c.
b b
5. All rational numbers are either _____________ decimals or non-terminating recurring.

6. An example of a number that is rational, integer, whole but not natural is _____________.

Answer in One Word or a Line
–1
1. What is the additive inverse of ?
4
2. What is the sum of a rational number and its additive inverse?
3
3. What is the multiplicative inverse of ?
4
4. A rational number is terminating if the denominator is expressible as prime factors of which
numbers?
7
5. Find all rational numbers in standard form having absolute value 11 .
6. Which is the smallest rational number?
7. What do we get when a non-zero rational number is divided by itself?

let’s evaluate
1. Identify the positive and negative rational numbers.

3 –8 –17 , 3 – –6
,
,
4 9 –21 –8 10

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