283-286-83+86-55
= (283-83)+(286+55)-86
= 200+ 231-86=345
C) 38x(27-44) -27 x (38-44)
= 38x27-38x44-27x38-27x44
=(38x27-27x38) + (38x44-27x44)
=0+484
=484
\(283-286-83+86-55\)
\(=\left(283-83\right)+\left(-286+86\right)+\left(-55\right)\)
\(=200+\left(-200\right)+\left(-55\right)\)
\(=\left(-55\right)\)
c) \(38\times\left(27-44\right)-27\times\left(38-44\right)\)
\(=38\times27-38\times44-27\times38+27\times44\)
\(=\left(38\times27-27\times38\right)+\left(27\times44-38\times44\right)\)
\(=0+44\times\left(27-38\right)\)
\(=44\times\left(27-38\right)\)
\(=44\times\left(-11\right)\)
\(=\left(-484\right)\)
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