The problem asks to verify if the sum of the first 20 odd numbers is 400.
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 = $n^2$
In this case, we need the sum of the first 20 odd numbers, so '$n = 20$'.
Using the formula:
Sum = $20^2 = 20 \times 20 = 400$
The calculated sum of the first 20 odd numbers is 400.
The student's answer was 400.
Therefore, the student's answer is correct.
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 of the following statement is TRUE for Whole Numbers?
What is the Highest Common Factor of 2 3× 3 5and 3 3× 5 2?
Four prime numbers are arranged in ascending order. The product of the first three numbers is 255 and that of the last three is 1955. The largest prime number is:
Find the number of all prime numbers less than 55.
Value of the square root of \(\frac{36.1}{102.4}\) is:
For any natural number n, 6n - 5n always ends with