Question

Tinh nhanh

a) 19.64+76.34=

b) 35.12+65.13

c)136.68+16.272

b) ( 2+4+6+...+100).(36.333- 108.111)

e) 19991999.1998-19981998.1999=

f) 2014.2014-2016:2012

h) (124.237+152) : ( 870+ 235.122)

Answer 1

a) 19.64+76.34=19.64+19.4.34=19.(64+136)=19.200=3800

b) 35.12+65.13=35.12+65.12+65=12.(35+65)+65=12.100+65=1265

c) 136.68+16.272=136.68+32.136=136.(68+32)=136.100=13600

d) ( 2+4+6+...+100).(36.333 - 108.111)=(....).(108.111 - 108.111)=(....).0=0

 

Answer 2

a) 19. 64+76.34

=19 . 2. 32+ 38.2 . 34

=38.32+38.68

=38. (32+68)

=38.100

=3 800

b)35.12+65.13

=35.12+65.(12+1)

=35.12+65.12+65

=12.(35+65)+65

=12.100+65

=1 200 +65

=1265

Answer 3

19x64+19x34

=19x(64+34)

=19x98

=19x(100-2)

=19x100-19x2

=1900-38

=1862

Answer 4

a =3 800

b = 1265

hok tốt

Answer 5

e)19991999.1998-19981998.1999

=1999.10001.1998-1998.10001.1999

=0.