Question

tính nhanh

a) 2017 x 0,7 + 2017 x 20% + 201,7

b) 20,15 x 23 + 76 x 20,15 + 20,15

Answer 1

a)2017x0,7+2017x0,2+2017x0,1

=2017x(0,7+0,2+0,1)

=2017x1

=2017

b)=20,15x(23+76+1)

=20,15x100

=2015

Answer 2

a) 2017 x 0,7 + 2017 x 20% + 201,7

= 2017 x 0,7 + 2017 x 0,2 + 2017 x 0,1

= 2017 x ( 0,7 + 0,2 + 0,1)

= 2017 x 1

= 2017

b) 20,15 x 23 + 76 x 20,15 + 20,15

= 20,15 x 23 + 76 x 20,15 + 20,15 x 1

= 20,15 x ( 23 + 76 + 1)

= 20,15 x 100

= 2015