Question
What is the average of the squares of the first 25 natural
numbers?Solution
Sum of squares of first 'n' natural numbers = n × (n + 1) × (2n + 1) ÷ 6
So, average = n × (n + 1) × (2n + 1) ÷ 6n = (n + 1) × (2n + 1) ÷ 6
= (25 + 1) × (2 × 25 + 1) ÷ 6
= 26 × 51 ÷ 6
= 221
564.932 + 849.029 – 425.08 = 612.095 + ?
999.99 + 99.99 + 99= ?
A sum of ₹60,000 is invested at a compound interest rate of 'x%' per annum, compounded annually, and grows to ₹75,264 in 2 ye...
What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)...
³√? × 33.97 + 59.99 × 28.9 – 48.98 × 21.42 = 1085.344
1279.98 ÷ 40.48 × 10.12 = ? × 2.16
(124.901) × (11.93) + 219.95 = ? + 114.891 × 13.90
What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)...
Relevant for Exams:
