5760:80=268-196
5760:80=72; 268-196=72;
Равенство верно;
438*40=9806+8514
438*40=17520; 9806+8514=18320;
Равенство неверно.
3(целых)<span>3/8</span> × 1(целых)<span>1/15</span> = <span>3 + 3·8/8</span> × <span>1 + 1·15/15</span> = <span>27/8</span> × <span>16/15</span> = <span>27·16/8·15</span> = <span>432/120</span> = <span><span>18·24/</span><span>5·24</span></span> = <span>18/5</span> = <span>3 + 3·55</span> = 3(целых)<span>3/5</span> = 3.6
S= 2(Sa+Sb+Sc)= 2(ab+<span> bc</span>+<span> ac</span><span>)
S = 2(0.75*1,15+1,15*1,8+1,8*0,75)=2(0,8625+2,07+1,35)=
=2*4,2825=8,565 м</span>² = 856,5 см²