Question

1/2.3 + 1/3.4 + 1/4.5 + ... + 1/19.20 = ...
A. 9/10
B. 19/20
C. 9/20
D. 19/10
E. 1/19​

Answer 1

Jawaban:

1/2.3+1/3.4+1/4.5+…………1/19.20

= 1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+………..+1/19-1/20

= 1/2-1/20

= 9/20

Answer 2

Jawaban:

✍cara penyelesaiannya✍

=1/2.3 + 1/3.4 + 1/4.5 + ...1/19.20

=1/2-1/3-1/3-1/4-1/4-1/5-1/5-1/6 +...1/19-1/20

=1/2-1/20

=A. 9/10

✍cara penyelesaiannya✍