Extra Questions for Class 7 Maths Chapter 4: Expressions Using Letter-Numbers – HOTS

Fresh HOTS (Higher Order Thinking Skills) practice questions for Class 7 Maths Chapter 4 “Expressions Using Letter-Numbers”, designed to test deeper understanding beyond the textbook exercises. These Class 7 Mathematics Chapter 4 important questions are handy for last-minute exam practice.

Last Updated: September 23, 2026

Q1. Simplify: 5x − 3(2x − 4) + 7

Answer: 5x − 6x + 12 + 7 = −x + 19

Q2. If a = 3 and b = −2, evaluate 4a − 3b + 2ab.

Answer: 4(3) − 3(−2) + 2(3)(−2) = 12 + 6 − 12 = 6

Q3. Assertion-Reason — Assertion (A): The expression 3x + 2y has 2 terms. Reason (R): Terms in an algebraic…

Assertion (A): The expression 3x + 2y has 2 terms.
Reason (R): Terms in an algebraic expression are separated by + or − signs.

Answer: Both A and R are true, and R correctly explains A.

Q4. A shopkeeper sells notebooks at Rs. 25 each and pens at Rs. 10 each. Write an expression for the total cost of n notebooks and p pens, then find the cost for 6 notebooks and 4 pens.

Answer: Expression: 25n + 10p. For n=6, p=4: 25(6)+10(4) = 150+40 = Rs. 190

Q5. Spot the error — A student simplified 2(x+3) − (x−1) as "2x+3−x−1 = x+2". Find and correct the…

A student simplified 2(x+3) − (x−1) as “2x+3−x−1 = x+2”. Find and correct the error.

Answer: The student forgot to distribute the 2 to both terms and applied the wrong sign to −(x−1). Correct working: 2x+6−x+1 = x + 7

Q6. The perimeter of a regular octagon (8 equal sides) with side length s is given by which expression? Find the perimeter when s = 6 cm.

Answer: Perimeter = 8s. For s=6: 8×6 = 48 cm

Q7. Subtract (5x − 3y + 8) from (9x + 2y − 4).

Answer: (9x+2y−4) − (5x−3y+8) = 9x−5x+2y+3y−4−8 = 4x + 5y − 12

Q8. A matchstick pattern adds 5 sticks for every new triangle after the first, which uses 3 sticks. Write a general expression for n triangles, and find the number of matchsticks for 12 triangles.

Answer: Expression: 3 + 5(n−1) = 5n − 2. For n=12: 5(12)−2 = 60−2 = 58 matchsticks

Q9. If the sum of two expressions is 7x − 3y and one of them is 4x + 2y, find the other expression.

Answer: Other expression = (7x−3y) − (4x+2y) = 3x − 5y

Q10. Sequence puzzle: the nth term of a pattern is 3n − 2. What is the 25th term, and which term equals 100?

Answer: 25th term = 3(25)−2 = 75−2 = 73. For 3n−2=100: 3n=102, n=34th term

NCERT Solutions: Class 7 Maths Chapter 4

Revision Notes: Class 7 Maths Chapter 4 Revision Notes

Frequently Asked Questions

How would you write an algebraic expression for five more than three times a number?
This phrase translates to the expression 3x plus 5, where x represents the unknown number, since three times the number is written as 3x and five more than that value is added on afterward.

Why can two algebraic expressions that look different sometimes represent the same value?
Two expressions can be equivalent if one can be simplified or rearranged using rules like the distributive law or combining like terms, to become identical to the other, even though written differently at first.

Written by Satish

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