29-32+27=56-32=24
Ответ:24
<span>.......................................................73000</span>
7+8+9+....+56=S56-S6
Найдем S56
a1=1a56=56
Sn=(a1+an)*n/2
S56=((1+56)*56/2=57*28=1596
найдем S6
a1=1,a6=6
Sn=(a1+an)*n/2
S6=(1+6)*6/2=7*3=21
S56-S6=1596-21=1575