Question

10. (-2020) - (10 - 2020)

11. (+879) - [3009 - (-879)] - 1991

12. 53 - {135 + [+74 + 53 - (-35 - 26)]}

Answer 1

10. \(\left(-2020\right)-\left(20-2020\right)\)
\(=\left(-2020\right)-\left(-2000\right)\)
\(=-20\)

11. \(\left(+879\right)-\left[3009-\left(-879\right)\right]-1991\)
\(=879-3888-1991\)
\(=-5000\)

12. \(53-\left\{135+\left[+74+53-\left(-35-26\right)\right]\right\}\)
\(=53-\left\{135+\left[127-\left(-61\right)\right]\right\}\)
\(=53-\left\{135+188\right\}\)
\(=53-323\)
\(=-270\)

Answer 2

10. -2020 - 10 + 2020 = -10

11. 879 - ( 3009 + 879 ) - 1991 = 879 - 3009 - 879 - 1991 = -3009 - 1991 = -5000

12. 53 - (135 + 74 + 53 + 35 + 26 ) = 53 - 135 -74 -53 - 35 - 26 = -135 - 74 - 35 - 26 = -( 135 + 35 ) - ( 74 + 26 ) = - 170 - 100 = -270

Answer 3

` (-2020) - (10 - 2020)`

` = -2020 - 10 + 2020`

` =(-2020 + 2020) - 10`

` = 0 -10`

` = -10`

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` (+879) - [3009 - (-879)] - 1991`

` = 879 - (3009 + 879) - 1991`

` = 879 - 3009 - 879 - 1991`

` = ( 879 - 879) - 3009 - 1991`

` = 0 - 3009 - 1991`

`= -5000`

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` 53 - {135 + [+74 + 53 - (-35 - 26)]}`

` = 53 - { 135 + [ 74 + 53 - (-61) ] }`

` = 53 - { 135 + [ 74 + 53 +61]}`

` =53 - { 135 +188 }`

` = 53 - 323`

` = -270`

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`#BaoL i n h`