Mathematics
Sum of first n natural numbers
Practice questions
If (S_n=5050), what is the value of (S_{n-10})?What is the ratio of the sums of the first (45) and first (30) natural numbers?If (S_n-S_{n-2}=101), what is the value of (S_n)?What is the sum of natural numbers from (15) to (45)?If the sum of the first (n) natural numbers is (S_n), what is (S_{n+1}-S_{n-1}) equal to?What is the difference between the sums of the first (72) and first (48) natural numbers?When is the sum \(S_n\) of the first n natural numbers odd?If (S_n=1081), what is the value of (S_{n+4}-S_n)?What will be the sum of natural numbers from (40) to (80)?If (S_n-S_{50}=1575), what is the value of (n)?Under which condition will the sum of the first n natural numbers be an even number?Which condition is necessary and sufficient for a positive integer \(T\) to be the sum of the first \(n\) natural numbers for some positive integer \(n\)?If (S_{n+2}-S_n=155), what is the value of (n)?A student added numbers from (1) to (120) and then subtracted the sum from (1) to (80). What will be the result?What is the ratio of the sums of the first (90) and first (60) natural numbers?If (S_n=3655), what will be (S_n-S_{n-4})?If a positive integer \(S\) can be written as the sum of the first \(n\) natural numbers, which of the following quantities must be an odd perfect square?What is the sum of natural numbers from (25) to (75)?If \(S_n\) is the sum of the first \(n\) natural numbers, which recurrence relation is always correct for \(n\ge2\)?What is half of the sum of the first (84) natural numbers?