Question

1. [(450-25x2):4 +(250+250+160:2)]:5 2.[3x (47x5-25x9) +a] +2=160 3. {12+3 x[20-2 x (7-10:5)] -13} x10= Rezolvati-mi astea va rog!!

Answer 1

1.

[ ( 450 - 25 x 2 ) : 4 + ( 250 + 250 + 160 : 2 ) ] : 5 = 136

= [ ( 450 - 50 ) : 4 + ( 500 + 80 ) ] : 5 =

= ( 400 : 4 + 580 ) : 5 =

= ( 100 + 580 ) : 5 =

= 680 : 5 =

= 136

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2.

[ 3 x  ( 47 x 5 - 25 x 9 ) + a ] + 2 = 160

[ 3 x ( 235 - 225 ) + a ] = 160 - 2

3 x 10 + a = 158

30 + a = 158

a = 158 - 30

a = 128

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3.

{ 12 + 3 x [ 20 - 2 x ( 7 - 10 : 5 ) ]  - 13 } x 10 =  290

= { 12 + 3 x [ 20 - 2 x ( 7 - 2 ) ] - 13 } x 10 =

= [ 12 + 3 x ( 20 - 2 x 5 ) - 13 ] x 10 =

= [ 12 + 3 x ( 20 - 10 ) - 13] x 10 =

= ( 12 + 3 x 10 - 13 ] x 10 =

= ( 12 + 30 - 13 ) x 10 =

= ( 42 - 13 ) x 10 =

= 29 x 10 =

= 290