# Category Archives: School Learning

Question 1. If nC8=nC2, find nC2. Solution:  We know that, nCr=nC(n-r) For the given question, r=8 and n-r=2 Hence, n=r+(n-r)=8+2=10 OR Using formula (1), nC8=nC(n-r) 8(n-8)=2(n-2) … Read More
Question 1: A wooden bookshelf has external dimensions as follows: Height = 110cm, Depth = 25cm, Breadth = 85cm (see fig. 13.31). The thickness of… Read More
Question 1: Given A = {1, 2, 3}, B = {3, 4}, C = {4, 5, 6}, find (A × B) ∩ (B × C).… Read More
Chapter 12 Percentage – Exercise 12.2 | Set 1 Question 14. An alloy of tin and copper consists of 15 parts of tin and 105… Read More
Question 1. Find:(i) 22% of 120(ii) 25% of Rs 1000(iii) 25% of 10 kg(iv) 16.5% of 5000 meter(v) 135% of 80 cm(vi) 2.5% of 10000… Read More
Question 1. Which of the following are examples of empty set? (i) Set of all even natural numbers divisible by 5. (ii) Set of all… Read More
Question 1. Find the square root of : (i) 441/961 (ii) 324/841 (iii) 4 29⁄29  (iv) 2 14⁄25  (v) 2 137⁄196     (vi) 23… Read More
Question 1. Find the square root of each of the following correct to three places of decimal. i) 5            … Read More