a) 9 . 24 . 25
= 9 . 600
= 5400
b) 12 . 125 . 5 = (12 . 5) . 125
= 60 . 125 =7500
c) 64 . 125 . 875= 8000 . 875 = 7000000
d) 425 . 7 . 4 - 170 . 60 = 1700 . 7 - 170 . 60
= 170 . (10 . 7) - 170 . 60
= 170 . 70 - 170 . 60
= 170 . (70 - 60)
= 170 . 10 = 1700
a, 9 . 24. 25 = 9. ( 25.24 ) = 9 . 600 = 5400
b, 12.125.5 = 1500.5 = 7500
c , 64 . 125 . 5 = ( 64 . 125 ) . 5 = 8000 . 5 = 40000
d, 425 . 7 . 4 - 170 . 60 = 1700 . 7 - 10200 = 11900 - 10200 = 1700
e , 8.9.14 + 6 . 7 .13 + 19 . 4 . 18 = 1008 + 546 + 1368 = 2922
\(8.9.14+6.7.12+19.4.18\)
\(=8.3.3.14+42.12+19.2.2.18\)
\(=24.42+42.12+38.36\)
\(=42.\left(24+12\right)+38.36\)
\(=42.36+38.36\)
\(=36.\left(42+38\right)\)
\(=36.90\)
\(=3240\)
