Question

Bài 1 tính thep  tổng sau :

 1/7 + 1/14 + 1/28 + 1/56 + 1/112 

Viết cả lời giải giúp mình nhé 

Answer 1

Answer 2

16/112 + 8/112 + 4/112 + 2/112 + 1/112

= 31/112

Answer 3

\(\dfrac{1}{7}+\dfrac{1}{14}+\dfrac{1}{28}+\dfrac{1}{56}+\dfrac{1}{112}\)

\(=\dfrac{1\times16}{7\times16}+\dfrac{1\times8}{14\times8}+\dfrac{1\times4}{28\times4}+\dfrac{1\times2}{56\times2}+\dfrac{1\times1}{112\times1}\)

\(=\dfrac{16}{112}+\dfrac{8}{112}+\dfrac{4}{112}+\dfrac{2}{112}+\dfrac{1}{112}\)

\(=\dfrac{28}{112}+\dfrac{2}{112}+\dfrac{1}{112}\)

\(=\dfrac{31}{112}\)

Answer 4

=31/112