Надо) а 74,7*2/21+(-105,3)*2 3/,3)*2/21-2 3/7*74,7. - вопрос №28009717472211053233221237747611023910109 от sasharuf2000 12.04.2021 11:54

Question

Алгебра: Надо) а 74,7*2/21+(-105,3)*2 3/,3)*2/21-2 3/7*74,7. б 6 1/10*2,391-0,109*1 5/6-1 5/6*2,391+0,109*6 1/10

sasharuf2000 · Answer

а )74,7*2/21+(-105,3)*2 3/7-(-105,3)*2/21-2 3/7*74,7=
=2/21*(74,7+105,3)-2 3/7(105,3+74,7)=180*(2/21-2 3/7)=180*(2/21-2 9/21)=
=180*(-2 1/3)=-420
б) 6 1/10*2,391-0,109*1 5/6-1 5/6*2,391+0,109*6 1/10 =
=6 1/10*(2,391+0,109)-1 5/6*(0,109+2,391)=2,5*(6 1/10-1 5/6)=2,5*(6 3/30-1 25/30)=
=2,5*(5 33/30-1 25/30)=2,5*4 4/15=5/2*64/15=32/3=10 2/3