8th Standard Syllabus & Materials
8th Standard
TN 8th Tamil இயல் 3 - கல்வி கரையில - வினைமுற்று Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - மயங்கொலிகள் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை -பட்டமரம் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - இயற்கையை போற்றுவோம் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 1 - தமிழ் இன்பம் - ஆழிக்கு இணை Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2-ஈடில்லா இயற்கை - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
Published on: 30/08/2019
Rational Numbers
Download Tamil Nadu 8th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test1.
Subtract \(\left( -2\frac { 6 }{ 11 } \right) \) from \(\left( -4\frac { 5 }{ 22 } \right) \)
2.
Reduce to the standard form
\(\frac { -18 }{ -42 } \)
3.
Reduce to the standard form
\(\frac { 48 }{ -84 } \)
4.
Write the following decimal numbers as rationals.
1.15
5.
If -3 x \(\frac { -6 }{ 11 } \) = \(\frac { -6 }{ 11 } \times x\) is _______________
6.
The multiplicative inverse of \(2\frac { 3 }{ 5 } \) is _____________
7.
The value of \(\left( \frac { -15 }{ 23 } \right) \div \left( \frac { +30 }{ -46 } \right) \) is _____________
8.
Associative property is not true for subtraction of rational numbers.
9.
\(\frac { -7 }{ 8 } \times \frac { -23 }{ 27 } =\frac { -23 }{ 27 } \times \frac { -7 }{ 8 } \) illustrates the closure property of rational numbers
10.
The rational numbers that are equal to their additive inverses are 0 and –1.
11.
Find the standard form of \(\frac{27}{18}\)
12.
Write four rational numbers equivalent to
\(\frac { 8 }{ 9 } \)
13.
Write four rational numbers equivalent to
\(\frac { -7 }{ 6 } \)
14.
List five rational numbers between
–1.2 and -2.3
15.
Multiplicative inverse of 0 (is)
0
1
-1
does not exist
16.
\(\frac { 3 }{ 4 } \div \left( \frac { 5 }{ 8 } +\frac { 1 }{ 2 } \right) \) =
\(\frac { 13 }{ 10 } \)
\(\frac { 2 }{ 3 } \)
\(\frac { 3 }{ 2 } \)
\(\frac { 5 }{ 8 } \)
17.
\(\frac { -5 }{ 4 } \) is a rational number which lies between
0 and \(\frac { -5 }{ 4 } \)
-1 and 0
–1 and –2
–4 and –5
18.
Which of the following rational numbers is the greatest?
\(\frac { -17 }{ 24 } \)
\(\frac { -13 }{ 16 } \)
\(\frac { 7 }{ -8 } \)
\(\frac { -31 }{ 32 } \)
1.
Now, \(\left( -4\frac { 5 }{ 22 } \right) -\left( -2\frac { 6 }{ 11 } \right) \)
= \(\frac { -93 }{ 22 } -\left( \frac { -28 }{ 11 } \right) \)
= \(\frac { -93 }{ 22 } +\frac { 28 }{ 11 } \)
= \(\frac { -93+28\times 2 }{ 22 } \)
= \(\frac { -93+56 }{ 22 } =\frac { -37 }{ 22 } =-1\frac { 15 }{ 22 } \)
2.
Method 1:
\(\frac { -18 }{ -42 } =\frac { -18\div (-2) }{ -42\div (-2) } =\frac { 9\div 3 }{ 21\div 3 } =\frac { 3 }{ 7 } \) (dividing by –2 and 3 successively)
Method 2:
The HCF of 18 and 42 is 6 (Find it). Thus, we can get its standard form by dividing it by 6.
\(\frac { -18 }{ -42 } =\frac { -18\times (-1) }{ -42\times (-1) } =\frac { 18 }{ 42 } =\frac { 18\div 6 }{ 42\div 6 } =\frac { 3 }{ 7 } \)
3.
Method 1:
\(\frac { 48 }{ -84 } =\frac { 48\div (-2) }{ -84\div (-2) } =\frac { -24\div 2 }{ 42\div 2 } =\frac { -12\div 3 }{ 21\div 3 } =\frac { -4 }{ 7 } \) (dividing by –2, 2 and 3 successively)
Method 2:
The HCF of 48 and 84 is 12 (Find it). Thus, we can get its standard form by dividing it by -12.
\(=\frac { 48\div (-12) }{ -84\div (-12) } =\frac { -4 }{ 7 } \)
4.
\(1.15=\frac { 115 }{ 100 } =\frac { 23 }{ 10 } =1\frac { 3 }{ 20 } \)
5.
( )
-3
6.
( )
\(\frac { 5 }{ 13 } \)
7.
( )
1
8.
(a)
9.
(b)
10.
(b)
11.
\(\\ \\ \frac { 27 }{ 18 } =1\frac { 9 }{ 18 } =1\frac { 1 }{ 2 } \)
12.
\(\frac { 8 }{ 9 } =\frac { 8\times 2 }{ 9\times 2 } =\frac { 16 }{ 18 } \)
\(\frac { 8 }{ 9 } =\frac { 8\times 3 }{ 9\times 3 } =\frac { 24 }{ 27 } \)
\(\frac { 8 }{ 9 } =\frac { 8\times 4 }{ 9\times 4 } =\frac { 32 }{ 36 } \)
\(\frac { 8 }{ 9 } =\frac { 8\times 5 }{ 9\times 5 } =\frac { 40 }{ 45 } \)
Four equivalent rational numbers of \(\frac { 8 }{ 9 } \) are \( \frac { 16 }{ 18 } ,\frac { 24 }{ 27 } ,\frac { 32 }{ 36 } ,\frac { 40 }{ 45 } \)
13.
\(\frac { 7 }{ -6 } =\frac { 7\times 2 }{ -6\times 2 } =\frac { 14 }{ -12 } \)
\(\frac { 7 }{ -6 } =\frac { 7\times 3 }{ -6\times 3 } =\frac { 21 }{ -18 } \)
\(\frac { 7 }{ -6 } =\frac { 7\times 4 }{ -6\times 4 } =\frac { 28 }{ -24 } \)
\(\frac { 7 }{ -6 } =\frac { 7\times 5 }{ -6\times 5 } =\frac { 35 }{ -30 } \)
Four equivalent rational numbers of \(\frac { -7 }{ 6 } \) are \(\frac { 14 }{ -12 } ,\frac { 21 }{ -18 } ,\frac { 28 }{ -24 } ,\frac { 35 }{ -30 } \)
14.
–1.2 and -2.3
\(-1.2=\frac { -1.2\times 10 }{ 1\times 10 } =\frac { -12 }{ 10 } \)
\(-2.3=\frac { -2.3\times 10 }{ 1\times 10 } =\frac { -23 }{ 10 } \)
∴ Five rational numbers between -1.2\(\\ \\ (=\frac { -12 }{ 10 } )\) and -2.3 \((=\frac { -23 }{ 10 } )\) are \(\frac { -21 }{ 10 } ,\frac { -20 }{ 10 } ,\frac { -15 }{ 10 } ,\frac { -14 }{ 10 } ,\frac { -13 }{ 10 } \)
15.
(d)
does not exist
16.
(b)
\(\frac { 2 }{ 3 } \)
17.
(c)
–1 and –2
18.
(a)
\(\frac { -17 }{ 24 } \)
8th Standard Syllabus & Materials
8th Standard
TN 8th Tamil இயல் 3 - கல்வி கரையில - பாடறிந்து ஒழுகுதல் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 3-கல்வி கரையில - பல்துறைக் கல்வி Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 3-கல்வி கரையில - புத்தியைத் தீட்டு Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - தமிழர் மருத்துவம் ( நேர்காணல்) Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 8th Standard Subjects
Tamilnadu Stateboard Standards
