How do I proceed to solve this question?
I Do understand the question now.
Had been going about it the wrong way
Solution:
total number of blocks: (r+1) *(r)
4th row=(r)
7th column = (r+1)
answer= total - 4th row - 7th column +1
adding 1 because of the intersecting element
Answer is A
So , basically we need to remove 1 row and 1 column from the gameboard .
Initially, No. of rows = r & No. of columns = r+1, Now, removing 1 row and 1 column will make the No. of rows = r-1 and No. of columns = r. Finally, its asking us to find total No. of squares which is Rows x Columns , which equals to (r-1) x (r) = r^2-r
method 2: Choosing numbers ,
Let rows = 11(r) and columns = 12(r+1), Now, removing 1 row and 1 column thus, rows = 10 and columns = 11. Squares on board= Rows x Columns = 110. Now, pulling the value of our r= 11 in the answer choices and seeing which one will results us in 110.’
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