What is the function of the soft pedal on an upright piano?

New pianos are a bit different as they have three strings for each note for most notes of the piano. So, when you press the soft pedal it will move the hammers over and they won't strike the strings in the middle of the hammers, so it produces a mellower tone. True una corda or soft-pedals only exist on grand pianos.

perimeter = 2l +2w, divide total perimeter by 2 for total length of 1 side and 1 width

172/2 = 86 (  total for 1 side and 1 width)

86-24 = 62 (since length is 24 ft longer subtract 24 then divide by 2 for width)

62/2 = 31

width = 31 feet

length = 31 +24 = 55 feet

check: 31*2 = 62, 55*2 = 110,  110+62 = 172

i believe their role is to instruct certain sections on when they are to join and when they are to stop