Question #65c13

2 Answers
Apr 14, 2017

133/99

Explanation:

Recall (Sum of Geometric Series Formula):

a + ar + ar^2+ar^3+cdots=a/(1-r) if |r| < 1

We can view a repeated decimal as the sum of a geometric series.

1.343434...=1+[0.34+0.0034+0.000034+cdots]

=1+[34/100+34/100(1/100)+34/100(1/100)^2+cdots]

By applying the formula above with a=34/100 and r=1/100 starting with the second term,

=1+(34/100)/(1-1/100) =1+(34/100)/(99/100) =99/99+34/99=133/99

Apr 14, 2017

133/99

Explanation:

Obtain 2 equations with the same repeating part then subtract them.

"We can represent the repeated part by " 1.bar34

x=1.bar34to(1)larrcolor(red)" multiply by 100"

100x=134.bar34to(2)

"Subtract " (2)-(1)

(100x-x)=(134.bar34-1.bar34)

rArr99x=133larrcolor(red)" repeating part eliminated"

rArrx=133/99larrcolor(red)"in simplest form"