Mathematics
Sum of first n natural numbers
Practice questions
In a saving plan, (1) rupee is saved in the (1)st week and (49) rupees in the (49)th week. If the amount increases by (1) rupee each week, what is the total saving?What is (4) times the sum of the first (21) natural numbers?Why is the product \(n(n+1)\) always even in the formula \(S_n=\frac{n(n+1)}{2}\) for the sum of the first n natural numbers?What is the difference between the sum of the first (39) natural numbers and (39)?What is the sum of (23+24+25+\cdots+34)?For which (n) will (S_n-S_{n-1}=62)?Find the sum of the first (75) natural numbers.If (S_{18}=171), what will be the value of (S_{22})?What is obtained by adding (46), (47), and (48) to the sum of the first (45) natural numbers?What is the ratio of (S_{30}) to (S_{15})?In a triangular decoration, flowers are arranged in rows from (1) to (28). How many flowers are there in total?What is the value of (S_{64}-S_{63})?If the sum of the first (t) natural numbers is (231), what is the value of (t+5)?What will be the sum of the first (68) natural numbers?What is the value of (S_{13}+S_{16}+S_{20})?If (S_a=820) and (S_b=1035), what is (b-a)?What sum is obtained by adding (53+54+55) to (1+2+\cdots+52)?What is the sum of the first (80) natural numbers?Let \(S_n\) denote the sum of the first n natural numbers. What is \(S_{n+1}-S_n\) when the next natural number is included in the sum?Find the value of (S_{25}+S_{27}).