Algebraic Expression

A. Write algebraic expressions (1–35)

1. 7 more than a number
2. A number decreased by 12
3. 9 times a number
4. A number divided by 5
5. 4 less than twice a number
6. 3 more than five times a number
7. The sum of a number and 8, multiplied by 2
8. 15 subtracted from the product of 6 and a number
9. Twice the difference of a number and 7
10. A number increased by 9, then divided by 3
11. Perimeter of a square with side length x
12. Perimeter of a rectangle whose length is l and width is 8 cm less than length
13. Area of a rectangle with length l and breadth b
14. Age of Ravi 5 years ago if his present age is a years
15. Cost of 8 pens if one pen costs p rupees
16. Total money with Seema if she has ₹50 more than twice what Rahul has (let Rahul have r rupees)
17. Number of legs in 4 tables and 7 chairs (table has 4 legs, chair has 4 legs)
18. Total rupees if x 10-rupee notes and y 20-rupee notes
19. Temperature is now 4°C less than yesterday’s temperature t
20. Distance covered in 3 hours at speed v km/h
21. Sum of three consecutive numbers if the smallest is n
22. Sum of three consecutive even numbers if the middle one is m
23. Product of two consecutive integers if the smaller is k
24. 25 less than the product of 9 and a number
25. A number multiplied by itself
26. A number multiplied by itself and then add 15
27. 7 subtracted from the square of a number
28. Twice a number plus 11
29. Half of a number decreased by 4
30. 3 times the sum of a number and 6
31. The quotient when 48 is divided by a number
32. 5 more than one-third of a number
33. 4 fewer than seven times a number
34. The sum of twice a number and three times the same number
35. A number increased by 20% of itself (use decimal or fraction)

B. Substitute the value and evaluate (36–60)

Let x = 4, y = 7, z = 3, a = 10, b = 2

36. 5x + 8
37. 12 – 3y
38. 4x – 9
39. 2(x + 7)
40. 3(8 – y)
41. x² + 5
42. y² – 20
43. 2x²
44. x² + y²
45. (x + y)²
46. 7a – 4b
47. 9a ÷ 3
48. 15 – 2z
49. 4(x + y)
50. 6(z – 2)
51. xy + 12
52. 2xy
53. x² – y
54. 3x + 4y – 10
55. 20 – (x + y + z)
56. 5a – 3b + 2
57. ab + a + b
58. (a – b)²
59. 2x² + 3y
60. x³ ÷ 2 (x = 4)

C. Simplify the following expressions (61–85)

61. 7m + 4m
62. 12p – 5p
63. 9x + 3 – 2x
64. 15y – 8y + 7
65. 4a + 3b – a + 2b
66. 8k – 3k + 12 – 5
67. 2x + 5x – 9 + x
68. 17 – 6m + 2m – 4
69. 3(2p + 5)
70. 4(7 – 2q)
71. 6(3x + 4) – 5x
72. 2(5y – 3) + 4y
73. 9a – 2(a + 7)
74. 12 – 3(4 – b)
75. 5(2x + 1) – 3(x + 4)
76. 7m + 3(m – 2) + 4
77. 4x + 3(x – 5) – 2x
78. 10 – 2(3y – 1) + y
79. 2(3a + b) + 3(a – b)
80. 5(2p – q) – 2(p + 3q)
81. x + 3x + 2x – x
82. 8y – (2y + 5) + y
83. 4(3k – 2) + 5(2 – k)
84. 6(2m + 1) – 4(m – 3)
85. 3[4x – (2x + 5)]

D. Mixed word problems / form & evaluate (86–100)

86. One pencil costs ₹12. Write expression for cost of n pencils. Find cost of 9 pencils.
87. A number is 15 less than four times another number. If the smaller number is x, write expression for the larger number.
88. Reena’s age is three times the age of her brother. Brother’s age is b years. Write Reena’s age. If b = 6, how old is Reena?
89. A shop gives 3 free notebooks on purchase of 10 notebooks. Cost of one notebook is ₹25. Write expression for amount paid for m notebooks.
90. Perimeter of triangle is 48 cm. Two sides are x cm and (x + 5) cm. Write expression for third side.
91. A number multiplied by 6 gives 54 more than the same number. Write equation.
92. If 3 times a number plus 11 is 50, write the expression on left side.
93. Temperature dropped 7°C from yesterday. Today it is t°C. Yesterday’s temperature?
94. Salary of Amit is ₹1500 more than twice salary of Bunty (let Bunty’s salary = s). Write Amit’s salary.
95. In a class, number of girls is 4 more than twice number of boys. Let boys = b. Write total students.
96. Cost of 5 kg apples and 3 kg oranges is ₹(8x + 45). If x = 12, find total cost.
97. A rope is cut into 4 equal pieces. Each piece is (3y + 2) cm long. Write total length of rope.
98. After giving away 15 sweets, Meera has three times as many sweets as before giving. Let original sweets = s. Write equation.
99. A book has p pages. Ravi reads 18 pages every day. Write pages left after 4 days.
100. If a two-digit number has tens digit = d and units digit = e, write the number in algebraic form.