Ex. 19 . va rog repede . Clasa a VI-a
Dau coronița
Răspunsuri la întrebare
Răspuns:
Explicație pas cu pas:
19)
a) ( - 4) × ( - 213) × (+25) = (-4×25) ×(-213) = (-213)×(-100) = 213 000
-> am folosit asociativitatea, asociind primul cu al treilea factor
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b) 15 × ( - 117) × ( - 2) = (-117) × ( - 30 ) = 3 510
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c) ( - 2) × 37 × (+4) × ( - 125 ) = (-)×(-) × ( 2×4×125)× 37
= 37 × 1 000 = 37 000
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d) + 50 × ( - 17 ) × ( - 200 ) × ( - 3 ) =
= ( +) × ( - ) × ( - ) × ( - ) × ( 17 × 3 ) × ( 50 × 200 ) =
= + 51 × 10 000 =
= 510 000
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e) ( - 5) × ( - 217 ) × ( - 4 ) × ( - 10 ) = 43 400
= ( -) × ( - ) × ( - ) × ( - ) × 217 × ( 5 × 4 × 10 ) =
= + 217 × 200 =
= 43 400
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f) ( - 15 ) × 313 × ( -8) × ( - 20 ) =
= - (313 ×8 )× 300 =
= - 2504 × 300 =
= - 751 200