Question

Tính nhanh

1/2 +1/4+1/6+1/8+1/10+1/12+1/14

 

Answer 1

1/2 bang 1/4 suy ra

Answer 2

1/2+1/4+1/6+1/8+1/10+1/12+1/14

= 6/7

Answer 3

1/2 +1/4+1/6+1/8+1/10+1/12+1/14 =6/7

 

Answer 4

1/2 = 6/7 nhe ban

Answer 5

6/7 sai hoi tich

 

Answer 6

cộng tất cả các số lại có tổng 6/7

Answer 7

 1/2 + 1/4 +1/6 + 1/8 + 1/10 + 1/12 + 1/14

=3/4 + 1/6 + 1/8 + 1/10 + 1/12 + 1/14

=11/12 + 1/8 + 1/10 + 1/12 + 1/14

=25/24 + 1/10 + 1/12 + 1/14

= 137/120 + 1/12 + 1/14

= 49/40 + 1/14

=363/280