a,79.101=79.(100+1)
= 79.100 + 79
=7900 + 79 = 7979
b,(1999+2016)-1999 = 1999 - 1999 + 2016 = 0 + 2016 = 2016
c,81+250+19 =(81 + 19) + 250 = 100 + 250 = 350
d,165+79+135 =(165+135)+79=300+79=379
e,35.45+35.55=35.(45+55)
= 35.100
=3500
f,5.125.2.8=(5.2).(125.8)
= 10 . 1000
= 10 000
a) 79. 101
= 79 . (100 + 1)
= 79. 100 + 79
= 7 900 + 79
= 7 979
b) (1 999 + 2 016) - 1 999
= ( 1 999 - 1 999) + 2 016
= 0 + 2 016
= 2 016
c) 81 + 250 + 19
= (81 + 19) + 250
= 100 + 250
= 350
d) 165 + 79 + 135
= (165 + 135) + 79
= 300 + 79
= 379
e) 35 . 45 + 35 . 55
= 35 . (45 + 55)
= 35. 100
= 3 500
f) 5. 125 . 2. 8
= (5 . 2) . (125 . 8)
= 10 . 1 000
= 10 000
