Question

tính nhanh

50 + 100 + 50 + 40 + 10 + 10 + 40

Answer 1

50+100+50+40+10+10+40

=(50+50)+(40+40+10+10)+100

=100+100+100

=100.3

=300

nhae

Answer 2

50 + 100 + 50 + 40 + 10 + 10 + 40

= (50 + 50) + (40 + 10 + 10 + 40) + 100

=     100 + 100 + 100

=          300

Answer 3

=(50+100+50)+(40+10+10+40)

=200+100

=300

Answer 4

50+100+50+40+10+10+40

=150+100+50

=300