List of top Mathematics Questions asked in CBSE Class VIII

Subtract 4p2q – 3pq + 5pq2 – 8p + 7q – 10 from 18 – 3p – 11q + 5pq – 2pq2 + 5p2q
Find the product.
(i) (5 – 2x) (3 + x) 
(ii) (x + 7y) (7x – y) 
(iii) (a2+ b) (a + b2) 
(iv) (p2 – q2) (2p + q)
Solve and check result: \(x = \frac{4}{5}(x+10)\)
Add the following. l2 + m2, m2 + n2, n2 + l2, 2lm + 2mn + 2nl
Find the.
  1. Probability of the pointer stopping on D in (Question 1-(a))?
  2. Probability of getting an ace from a well shuffled deck of \(52\) playing cards?
  3. Probability of getting a red apple. (See figure below)
Image of Red Apples
Draw a rough figure of a quadrilateral that is not a parallelogram but has exactly two opposite angles of equal measure.
Solve and check result: \(8x + 4 = 3(x - 1) + 7\)
Top surface of a raised platform is in the shape of a regular octagon as shown in the figure. Find the area of the octagonal surface.
raised platform of a regular octagon
 
Subtract 4a – 7ab + 3b + 12 from 12a – 9ab + 5b – 3
Suppose 2 kg of sugar contains 9 x 106 crystals. How many sugar crystals are there in (i) 5 kg of sugar? (ii) 1.2 kg of sugar?
Factorise the following expressions 
  1.  \(7x - 42\) 
  2.  \(6p - 12q\) 
  3.  \(7a ^2 + 14a\) 
  4.  \(-16z + 20z ^3\) 
  5.  \(20l^ 2m + 30\, alm\) 
  6.  \(5x^ 2 y - 15xy^2\) 
  7.  \(10a^ 2 - 15b^ 2 + 20c^ 2 \)
  8.  \(-4a^ 2 + 4ab - 4 ca\) 
  9.  \(x ^2 yz + xy^2 z + xyz^2\)
  10.  \(ax^2 y + bxy^2 + cxyz\)
The lateral surface area of a hollow cylinder is 4224 cm2. It is cut along its height and formed a rectangular sheet of width 33 cm. Find the perimeter of rectangular sheet.
A 5 m 60 cm high vertical pole casts a shadow 3 m 20 cm long. Find at the same time -
(i) the length of the shadow cast by another pole 10 m 50 cm high
(ii) the height of a pole which casts a shadow 5 m long.
Factorise 
  1.  \(4p^ 2 - 9q ^2\) 
  2.  \(63a^ 2 - 112b ^2\) 
  3.  \(49x^ 2 - 36\) 
  4.  \(16x^ 5 - 144x^ 3\)
  5.  \((l + m)^ 2 - (l - m) ^2\) 
  6.  \(9x^ 2 y^ 2 - 16 \)
  7.  \((x^ 2 - 2xy + y^ 2 ) - z^ 2\) 
  8.  \(25a ^2 - 4b^ 2 + 28bc - 49c ^2\)
When a die is thrown, list the outcomes of an event of getting 
  1. (a) a prime number (b) not a prime number. 
  2. (a) a number greater than 5 (b) a number not greater than 5.
Factorise the following expressions. 
  1.  \(a^ 2 + 8a + 16 \)
  2. \(p^ 2 - 10p + 25 \)
  3. \(25m^2 + 30m + 9 \)
  4. \(49y^ 2 + 84yz + 36z ^2 \)
  5. \(4x^ 2 - 8x + 4 \)
  6. \(121b ^2 - 88bc + 16c ^2 \)
  7. \((l + m) ^2 - 4lm \) (Hint: Expand \((l + m) ^2 \) first)
  8.  \(a^ 4 + 2a ^2b ^2 + b^ 4\)
Complete the following table of products:
 

First monomial → Second monomial ↓

2x    

–5y

 3x2

– 4xy

7x 2 y

–9x 2 y 2

2x 

4x2

. . .

. . .

. . .

. . .

. . .

–5y

. . .

. . .

-15x2y

. . .

. . .

. . .

3x2

. . .

. . .

. . .

. . .

. . .

. . .

– 4xy

. . .

. . .

. . .

. . .

. . .

. . .

7x 2 y

. . .

. . .

. . .

. . .

. . .

. . .

–9x2 y2

. . .

. . .

. . .

. . .

. . .

. . .

Subtract 3xy + 5yz – 7zx from 5xy – 2yz – 2zx + 10xyz
Explain how a square is. 
  1. a quadrilateral 
  2. a parallelogram 
  3. a rhombus 
  4. a rectangle
Solve the linear equation: \(\frac{3t-2}{4}-\frac{2t+3}{3}=\frac{2}{3}-t\)
Simplify.
(i) (x2– 5) (x + 5) + 25
(ii) (a2+ 5) (b3+ 3) + 5
(iii) (t + s2) (t2 – s)
(iv) (a + b) (c – d) + (a – b) (c + d) + 2 (ac + bd)
(v) (x + y) (2x + y) + (x + 2y) (x – y)
(vi) (x + y) (x2– xy + y2)
(vii) (1.5x – 4y) (1.5x + 4y + 3) – 4.5x + 12y
(viii) (a + b + c) (a + b – c)
Find \(x\) in the following figures.
Polygon a   Polygon b
Carry out the multiplication of the expressions in each of the following pairs.
(i) 4p, q + r
(ii) ab, a – b
(iii) a + b, 7a²b²
(iv) a2 – 9, 4a
(v) pq + qr + rp, 0
Factorise 
  1. \(x^ 2 + xy + 8x + 8y\)
  2.  \(15xy - 6x + 5y - 2 \)
  3.  \(ax + bx - ay - by\) 
  4.  \(15pq + 15 + 9q + 25p\) 
  5.  \(z - 7 + 7xy - xyz\)
Add the following. a – b + ab, b – c + bc, c – a + ac.