Упр.540 ГДЗ Муравин 6 класс (Математика)
1) 19,6•2,5-(2,0625-1 5/12) :1/8;
2) ((15/28-11/36)•21/29-6 6/7 :(-16/21)) :(-16,5);
3) (5,05:1/40-2,8•5/6)•3+(-16)•(-0,1875);
4) (9 3/20-1,24) :2 1/3-(3/4+2 5/8) :(-0,625).
1) $$19{,}6\cdot 2{,}5-(2{,}0625-1\frac{5}{12}):\frac18$$
$$19{,}6\cdot 2{,}5=49$$
$$2{,}0625=2\frac{1}{16}$$
$$2\frac{1}{16}-1\frac{5}{12}=1+\frac{1}{16}-\frac{5}{12}=1+\frac{3-20}{48}=1-\frac{17}{48}=\frac{31}{48}$$
$$\frac{31}{48}:\frac18=\frac{31}{48}\cdot 8=\frac{31}{6}=5\frac16$$
$$49-5\frac16=43\frac56$$
2) $$\left(\left(\frac{15}{28}-\frac{11}{36}\right)\cdot\frac{21}{29}-6\frac67:\left(-\frac{16}{21}\right)\right):(-16{,}5)$$
$$\frac{15}{28}-\frac{11}{36}=\frac{135-77}{252}=\frac{58}{252}=\frac{29}{126}$$
$$\frac{29}{126}\cdot\frac{21}{29}=\frac{1}{6}$$
$$6\frac67=\frac{48}{7},\qquad \frac{48}{7}:\left(-\frac{16}{21}\right)=\frac{48}{7}\cdot\frac{21}{-16}=-9$$
$$\frac16-(-9)=\frac16+9=\frac{55}{6}$$
$$-16{,}5=-\frac{33}{2}$$
$$\frac{55}{6}:\left(-\frac{33}{2}\right)=\frac{55}{6}\cdot\frac{2}{-33}=-\frac{5}{9}$$
3) $$\left(5{,}05:\frac{1}{40}-2{,}8\cdot\frac56\right)\cdot 3+(-16)\cdot(-0{,}1875)$$
$$5{,}05:\frac{1}{40}=5{,}05\cdot 40=202$$
$$2{,}8\cdot\frac56=\frac{14}{5}\cdot\frac56=\frac73$$
$$202-\frac73=201\frac23$$
$$201\frac23\cdot 3=605$$
$$(-16)\cdot(-0{,}1875)=3$$
$$605+3=608$$
4) $$\left(9\frac{3}{20}-1{,}24\right):2\frac13-\left(\frac34+2\frac58\right):(-0{,}625)$$
$$9\frac{3}{20}-1{,}24=9\frac{15}{100}-1\frac{24}{100}=8\frac{91}{100}$$
$$2\frac13=\frac73,\qquad 8\frac{91}{100}:\frac73=8\frac{91}{100}\cdot\frac37=\frac{2673}{700}$$
$$\frac34+2\frac58=\frac34+2\frac58=\frac{6}{8}+\frac{21}{8}=\frac{27}{8}$$
$$-0{,}625=-\frac58,\qquad \frac{27}{8}:\left(-\frac58\right)=\frac{27}{8}\cdot\frac{8}{-5}=-\frac{27}{5}$$
$$\frac{2673}{700}-\left(-\frac{27}{5}\right)=\frac{2673}{700}+\frac{3780}{700}=\frac{6453}{700}=9\frac{153}{700}$$
Ответ
1) $$43\frac56$$; 2) $$-\frac59$$; 3) $$608$$; 4) $$9\frac{153}{700}$$.