2 × [ 576 -(75 + 324 : 3 - 9 × 7 + 844 :4)]:10=
= 2 x [ 576 - ( 75 + 108 - 63 + 211)] : 10 =
= 2 x [ 576 - ( 183 - 63 + 211) ] : 10 =
= 2 x [ 576 - ( 120 + 211)] : 10 =
= 2 x ( 576 - 331) : 10 =
= 2 x 245 : 10 =
= 490 : 10 =
= 49
b)
44 × [44 + 44 × 4 - ( 44 + 44 × 4 - 44 : 4)] - 44=440
= 44 × [ 44 + 176 - ( 44 + 176 - 11 )] - 44 =
= 44 x [ 220 - ( 220 - 11) ] - 44 =
= 44 x ( 220 - 209 ) - 44 =
= 44 x 11 - 44 =
= 484 - 44 =
= 440
c)
486 : [987 : 7 - ( 3 × 3 + 882 : 7)]=81
= 486 : [ 141 - ( 9 + 126) ]=
= 486 : ( 141 - 135) =
= 486 : 6 =
= 81