Aptitude - Decimal Fraction - Discussion

Because upside of that no is power by bar that's why we have to divide by 99.

3-2=1.
87-59=28.
3.87-2.59=1.28.

Why the all number divided by 99? Just tell.

Very good technique. Thanks to explain.

@Naveen

when 3.87 - 2.59 dot takes place Hundred so simply write 387/100-259/100 but in numerator 87(bar) is their so to less one number in denominator 3.87-2.59.

(3 + 0.87) - (2 + 0.59),
(3 + 87/99) - (2 + 59/99),
3 + 87/99- 2 - 59/99,
Next, step to separate
(3 - 2) + (87/99 - 59/99),
(1) + ((87-59)/99),
1 + (28/99).
Next step comparing with answers all answer in a fraction, so change it as
1.28(bar).

Why it is not like (387-3)/99 -(259-2)/99?

Then, 127/99,
Ans = 1.(bar of 27) or 1.27.

@Nagaraju.

Can we change the signs by opening the brackets as you explained in step 3 above?

3.87-2.59.
(3+87÷99)-(2+59÷99),
(297+87)÷99 -(198+59)÷99,
(384÷99)-(257÷99),
127÷99.

I don't know where I am wrong, can anyone explain?

Good solution and even short cut way is also so good.

@Vasu.

You reached till 127/99, Which is perfectly right, now to solve this further look at the options a) 1.20 and b) 1.2bar is no ways the answer.

Let's take c) 1.27bar .. solve this 1.27 bar can be written as 1+0.27 bar which is nothing but 1+27/99 now solve this you get 126/99 which is not what you got.

Now take option d) 1.28bar same as above this can be written as 1+0.28 bar which is 1+28/99 and solve this now, You get the Solution as 127/99 same as what you got. Hence option d)1.28bar is the right answer.

Hope it helped you.