How many squares do I have to draw in(10 x 10 grid) for the percentage of 57.74%??

There is obviously only 1 10x10 square. If we start with a 9x9 square in the top left corner, we can move it down 1, across 1 and back up 1, so there are 4 possible 9x9 squares.

For 8x8 we can move down 1, then 2 and we can move across 1 or 2 so that's 9 possible 8x8 squares.

For 7x7 we can go down 3 and across 3, so that's 4x4=16 possible squares.

The pattern is now clear the total number if squares is 1+4+9+16+…+100.

There's a formula for this, which I had to look up, but any the sum of the first n squared is 1/6n(n+1)(2n+1)1/6n(n+1)(2n+1), so the total number of squares is 10x11x21/6=5x11x7=385.

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for