\(a,1999-2000+1=\left(1999+1\right)-2000=2000-2000=0\\ b,450:5+550:5=\left(450+550\right):5=1000:5=200\\ c,188\times7+188\times4-188=188\times\left(7+4-1\right)=188\times10=1880\)
a,1999−2000+1=(1999+1)−2000=2000−2000=0b,450:5+550:5=(450+550):5=1000:5=200c,188×7+188×4−188=188×(7+4−1)=188×10=1880
a) 1999 - 2000 + 1
= ( 1999 + 1 ) - 2000
= 2000 - 2000
= 0
b) 450 : 5 + 550 : 5
= ( 450 + 550 ) : 5
= 1000 : 5
= 200
c) 188 x 7 + 188 x 4 - 188
= ( 7 + 4 - 1 ) x 188
= 10 x 188
= 1880
1999 - 2000 + 1 450 : 5 + 550 : 5 188 x 7 + 188 x 4 - 188
= (1999 + 1) - 2000 = (450 + 550) : 5 = 188 x 7 + 188 x 4 - 188 x 1
= 2000 - 2000 = 1000 : 5 = 188 x (7 + 4 - 1)
= 0 = 200 = 188 x 10
= 1880