0
To find the sum of the first 81 odd numbers, we can use the formula for the sum of an arithmetic series: Sn = n/2 * (2a + (n-1)d), where n is the number of terms, a is the first term, and d is the common difference. In this case, n = 81, a = 1 (first odd number), and d = 2 (since the difference between consecutive odd numbers is 2). Plugging these values into the formula, we get: S81 = 81/2 * (2(1) + (81-1)2) = 81/2 * (2 + 160) = 81/2 * 162 = 6561. Therefore, the sum of the first 81 odd numbers is 6561.
Still curious? Ask our experts.
Chat with our AI personalities
Rafa
Coach
Devin
Add your answer:
Earn +20 pts
What are the 9 odd numbers whose sum is 50 from 1 to 50?
To find the 9 odd numbers whose sum is 50 from 1 to 50, we can first calculate the sum of all odd numbers from 1 to 50, which is (50^2)/2 = 625. Next, we subtract the sum of the first 9 odd numbers (1+3+5+7+9+11+13+15+17 = 81) from the total sum, resulting in 625 - 81 = 544. Therefore, the 9 odd numbers whose sum is 50 from 1 to 50 are 19, 21, 23, 25, 27, 29, 31, 33, and 36.
How many odd whole numbers would have to be added to get a sum of 81?
3, 5, 7, 9, ... , 81.
The sum of two consecutive odd integers of 164?
81 + 83 = 164
Which is the odd number 16 36 64 27 81?
27 and 81 are the odd numbers. Since odd numbers are 1, 3, 5, 7 and 9, look at the last number and you will be able to tell if it's odd or even.
Find two numbers such that their sum is 108 and difference is 54?
27 and 81
