In the museum of 280 pictures. From them landscapes are 3 times more, than still lifes, and portraits there is so much how many landscapes and still lifes together. Define number of pictures of each look.

154
X carat. - still lifes of 3 carats. - landscapes (x the +3rd) carat. - portraits of Only 280 pictures. x the +3rd + x the +3rd =280 of the 8th =280 x =280:8 x =35 (carat.) - still lifes 35*3=105 (carat.) - landscapes 105+35=140 (carat.) - portretypust x - still lifes then the 3rd - landscapes And x the +3rd - portraits we work out the equation x the +3rd + x the +3rd = 280 of the 8th = 280 x = 35 still lifes = 35 landscapes = 3*35 = 105 portraits = 105+35 = 140
390
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