7 years ago
Help me solve this:
A group of 630 children are arranged for a group photograph session. Each row contains three fewer children than the row infront of it. What is the possible number of rows?
6 years, 11 months ago
Hi Avantika,
Let the number of children in the last row be 'and the number of rows be 'n'.
Now, we have an A.P with a common difference, d = 3.
We know that the sum of A.P = (0.5n)(2a+(n-1)d)
0.5n(2a+(n-1)d) = 630
2an + 3n^2-3n = 1260
Since the equation contains 2 unknown variables, it has infinite number of solutions.
You can take CAT quotient tests to practice problems daily.