Class 7 Maths Chapter 11 Questions and Answers - Free PDF Download
FAQs on NCERT Solutions For Class 7 Maths Chapter 11 Exponents And Powers Exercise 11.1 - 2025-26
1. What key topics are covered in Vedantu’s NCERT Solutions for Class 7 Maths Chapter 11, Exponents and Powers?
Our NCERT Solutions for Class 7 Maths Chapter 11 provide detailed, step-by-step answers for all exercises based on the CBSE 2025-26 syllabus. The main topics covered include:
- Understanding bases and exponents.
- Applying the laws of exponents for multiplication and division.
- Solving problems involving the power of a power rule.
- Simplifying expressions using multiple exponential laws.
- Expressing large numbers in standard form.
2. What is the correct step-by-step method to simplify an expression like (2⁵ ÷ 2³) × 2²?
To solve such problems correctly as per the NCERT methodology, you should follow these steps:
- Step 1: Solve the expression inside the brackets first. Apply the division law of exponents (aᵐ ÷ aⁿ = aᵐ⁻ⁿ). Here, 2⁵ ÷ 2³ becomes 2⁵⁻³ = 2².
- Step 2: Now, the expression is simplified to 2² × 2².
- Step 3: Apply the multiplication law of exponents (aᵐ × aⁿ = aᵐ⁺ⁿ). So, 2² × 2² becomes 2²⁺² = 2⁴.
- Step 4: Calculate the final value, which is 2 × 2 × 2 × 2 = 16.
Following this sequence ensures accuracy and correctly applies the rules of exponents.
3. Why is it important to show each step when solving problems using laws of exponents?
Showing each step is crucial for several reasons. Firstly, it helps in systematically applying the correct law of exponents (like for multiplication, division, or power of a power) without confusion. Secondly, in exams, marks are often awarded for the correct method, not just the final answer. A step-by-step solution clearly demonstrates your understanding of concepts like identifying the base, handling negative exponents, and simplifying correctly, which minimises calculation errors and helps secure full marks.
4. What is the correct method for expressing a number as a product of powers of its prime factors in Chapter 11?
The correct method involves prime factorisation. Let's take the number 72 as an example:
- Step 1: Start by dividing the number by the smallest prime number, which is 2. 72 ÷ 2 = 36.
- Step 2: Continue dividing the result by 2 until it's no longer possible. 36 ÷ 2 = 18; 18 ÷ 2 = 9.
- Step 3: Move to the next prime number, which is 3. 9 ÷ 3 = 3.
- Step 4: The prime factors are 2, 2, 2, 3, and 3.
- Step 5: Express these factors in exponential form by counting their occurrences. Since 2 appears three times (2³) and 3 appears twice (3²), the final expression is 72 = 2³ × 3².
5. How do the NCERT Solutions help differentiate between simplifying (-3)⁴ and -3⁴?
This is a common point of confusion that the NCERT solutions clarify. In (-3)⁴, the base is -3 and the exponent is 4. The entire base is multiplied four times: (-3) × (-3) × (-3) × (-3) = 81. In -3⁴, the exponent 4 applies only to the base 3, not the negative sign. So, you first calculate 3⁴ (which is 81) and then apply the negative sign, making the answer -81. The solutions demonstrate this distinction through step-wise examples, preventing common errors.
6. What is the standard procedure for comparing large numbers in exponential form, like 4³ and 3⁴?
The most reliable method shown in the NCERT solutions for comparing such numbers is to calculate their actual values. This approach avoids confusion when bases and exponents are different.
- First, calculate the value of 4³: 4 × 4 × 4 = 64.
- Next, calculate the value of 3⁴: 3 × 3 × 3 × 3 = 81.
- Finally, compare the results. Since 81 > 64, we can conclude that 3⁴ is greater than 4³.
For very large numbers where calculation is not feasible, solutions demonstrate using laws of exponents to simplify them to a comparable form.
7. How does mastering the methods in NCERT Solutions for Chapter 11 help in higher classes?
Mastering the step-by-step methods for exponents and powers in Class 7 builds a strong foundation for advanced topics in algebra and science. Concepts like scientific notation (standard form) are essential in Physics and Chemistry for representing astronomical distances or atomic sizes. The laws of exponents are fundamental to simplifying complex algebraic expressions, polynomial operations, and solving equations in Class 8 and beyond. A solid understanding from these NCERT solutions ensures you can handle more complex calculations with speed and accuracy later on.






















