The triangular garden below shows four plants (one each in 4 cells).

Add 6 more plants (one plant per cell) to make 5 rows of 4 plants each.

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Name the place which have only 7 letters. It's 4,5,6,7 are related to a dead cell and the first 1,2,3 are used by ladies.

5 + 5 + 5 = 550

Add ONE STRAIGHT LINE to the above to make the sum correct.