Răspuns:
Explicație pas cu pas:
a) 5 + 9 × 3 + 7 579 - 10 × 468 = 2 931
= 5 + 27 + 7 579 - 4 680 =
= 7 611 - 4 680 =
= 2 931
_________________________
b) 1 999 × 1 997 + 1 999 - 1 998 × 1 996 = 5 994
= 1 999 × ( 1 997 + 1 ) - 1 998 × 1 996 =
= 1 999 × 1 998 - 1 998 × 1 996 =
= 1 998 × ( 1 999 - 1 996 ) =
= 1 998 × 3 =
= 5 994
_____________________________
c) 2001 × 9 - 2 × 2001 + 7 × 103 = 14 728
= 2 001 × ( 9 - 2 ) + 7 × 103 =
= 2 001 × 7 + 7 × 103 =
= 7 × ( 2 001 + 103) =
= 7 × 2 104 =
= 14 728
_________________________
d) 3 021 × 3 018 + 3 018 - 3 022 × 3 015 = 9 066
= 3 018 × ( 3 021 + 1 ) - 3 022 × 3 015 =
= 3 018 × 3 022 - 3 022 × 3 015 =
= 3 022 × ( 3 018 - 3 015 ) =
= 3 022 × 3 =
= 9 066
