Question

1.Care este media aritmetică a nr
7,28 si 37??
2.Efectueaza calculul: 15 × 12 × 3 + 12×7 ×3 +12×3 ×13 . Va rog sa ma ajutati!

Answer 1

Ma = (7.28 + 37) : 2 = 44.28 : 2 = 22.14

15 × 12 × 3 + 12 × 7 × 3 + 12 × 3 × 13 =

= 12 x 3(15 + 7 + 13)

= 36 x 35

= 1260

Answer 2

1.

Ma = ( 7,28 + 37 ) : 2 

Ma = 44,28 : 2

Ma = 22,24

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2.

15 x 12 x 3 + 12 x 7 x 3 + 12 x 3 x 13 = 

= 180 x 3 + 12 x 7 x 3 + 12 x 3 x 13

= 540  + 12 x 7 x 3 + 12 x 3 x 13

= 540 + 84 x 3 + 12 x 3 x 13

= 540 + 252 + 12 x 3 x 13

= 540 + 252 + 36 x 13

= 540  + 252 + 468

= 792  + 468

= 1260

Sau mai simplu : 

15 x 12 x 3 + 12 x 7 x 3 + 12 x 3 x 13 = 

= 12 x 3( 15 + 7 + 13 ) 

= 12 x 3 x 35

= 36 x 35

= 1260