Runtime of for loop-Q2

Problem: Find the time complexity for a nested for loop.

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A() {
    int i, j, k ,n;
    for(i = 1; i <= n; i++) {
        for(j = 1; j <= i; j++) {
            for(k = 1; k < 100; k++) {
                System.out.println("hello world"); 
            }
        }
    }
}

For each iteration of $i$ the inner loop executes a 100 times.

$$1 \times 100 + 2 \times 100 + 3 \times 100 + 4 \times 100 + 5 \times 100 ... \\ 100 \times (1 + 2 + 3 + 4 + 5 \; + \; ...) \Rightarrow 100 \times\sum_{i=0}^n i \\ \sum_{i=0}^n i = \frac{n (n + 1)}{2} \Rightarrow \\ 100 \times\sum_{i=0}^n i = \frac{n (n + 1)}{2} \\ runtime = 100 \times \frac{n (n + 1)}{2}$$

Answer: $O(n^2)$