Question

Using an infinite geometric series for the repeating decimal 0.551¯¯¯¯¯¯¯¯, with ratio 11000, find integers a and b so that 0.551¯¯¯¯¯¯¯¯ can be written as the fraction ab. (Simplify this fraction as much as possible before putting in your answers.)

Answer 1

Answer:

Sum = 551/999

Where a = 551 and b = 999

The two integers are 551 and 999

Step-by-step explanation:

Given

Decimal = 0.551

Ratio = 1/1000

By repeating the decimal, we can write;

0.551 -bar = 0.551551551.....

0.551551551..... = 0.551 + 0.000551 + 0.000000551 + ....

= 551/1000 + 551/1000000 + 551/1000000000 + ......

= 551/10³ + 551/10^6 + 551/10^9 + .....

= n=0 Σ∝(551/10³)(1/10³)^n

Hence, the infinite geometrc series is Σ(551/10³)(1/10³)^n for n = 0 to

∝

Given the ratio of 1/1000

Let r = 1/1000

r = 1/10³

a = 551/10³

The sum is defined as follows;

a/(1-r)

Sum = 551/10³ / (1 - 1/10³)

Sum = 551/1000 ÷ 999/1000

Sum = 551/999

So, a/b = 551/999

Where a = 551 and b = 999

The two integers are 551 and 999