Question

Tính các tích sau một cách hợp lý:

a, 14.50

b, 16.125

c, 9.24.25

d, 12.125.54

e, 30.40.50.60

f, 64.125.875

Answer 1

`a,14 xx 50 = 2 xx 7 xx 50 = 100 xx 7 = 700`

`b, 16 xx 125 = 8 xx 125 xx 2 = 1000 xx 2 = 2000`

`c, 9 xx 24 xx 25 = 9 xx 6 xx 4 xx 25`

`= 54 xx 100`

`= 5400`

`d, 12 xx 125 xx 54`

`= 4 xx 3 xx 125 xx 27 xx 2`

`= 1000 xx 81`

`= 81000`

`e, 30 xx 40 xx 50 xx 60`

`= 3 xx 4 xx 5 xx 6 xx 10000`

`= 3600000`

`f, 64 xx 125 xx 875`

`= 2^6 xx 5^3 xx 5^3 xx 7`

`= 10^6 xx 7`

`= 7 000 000`

Answer 2

`a, 14.50=(14:2).(50.2) = 7 . 100 = 700`

`b, 16.125= (16 :4) . (125.4) = 4 . 500 = 2000`

`c, 9.24.25 = 9 . (24.25)=9.  600 = 5400`

`d, 12.125.54 = (12.125).54 = 1500 . 54 = 81000`

`e, 30.40.50.60 = (40.50).(30.60) = 2000 . 1800 = 3600000`

`f, 64.125.875 = (875.64).125 = 56000 . 125 = 7000000`