Verifying the Sum of First 20 Odd Numbers
The problem asks to verify if the sum of the first 20 odd numbers is 400.
Sum Formula for Odd Numbers
There's a direct formula to calculate the sum of the first '$n$' odd numbers. The sum is equal to the square of '$n$'.
Formula: Sum = $n^2$
Calculation for First 20 Odd Numbers
In this case, we need the sum of the first 20 odd numbers, so '$n = 20$'.
Using the formula:
Sum = $20^2 = 20 \times 20 = 400$
Conclusion
The calculated sum of the first 20 odd numbers is 400.
The student's answer was 400.
Therefore, the student's answer is correct.
Similar Questions
- Which of these is both an Integer and a Whole number?
- Which of the following is a non-zero number that belongs to every set: Whole, Integer, Rational, and Real?
- What is the smallest number that must be added to 2378 to make it a perfect square?
- Which of the following is a perfect square and an Integer?
- The set of real numbers includes which of the following?
In the following examples, a number is coded as three digits — representing the remainders when the number is divided by 3, 7, and 11, respectively.
Example 1: $53 \rightarrow 53 \div 3 = 17 \text{ R} 2$, $53 \div 7 = 7 \text{ R } 4$, $53 \div 11 = 4 \text{ R } 9 \rightarrow \text{ Code: } 2, 4, 9$
Example 2: $68 \rightarrow 68 \div 3 = 22 \text{ R} 2$, $68 \div 7 = 9 \text{ R } 5$, $68 \div 11 = 6 \text{ R } 2 \rightarrow \text{ Code: } 2, 5, 2$
By following this method, which is the least number which would have the code - 2, 2, 2?- Which roll number has only prime digits?
- Which roll number is a perfect cube?
- Which roll number has a digital root equal to 9? Digital root = sum of digits until one digit remains.
Which of the following statement is TRUE for Whole Numbers?
Important Questions from Number System
Consider the following statements :
1. (25)! + 1 is divisible by 26
2. (6)! + 1 is divisible by 7
Which of the above statements is/are correct ?
If the sum S is divided by 8, what is the remainder ?
If the sum S is divided by 60, what is the remainder ?
Find the sum of squares of the greatest value and the smallest value of K in the number so that the number 45082K is divisible by 3.
How many composite numbers are there from 53 to 97 ?
