# If A,B,C are the mechanism used seperately to reduce the wastage of the fuel by 30%, 40%, 10% What will be the fuel economy if they were used Combined?

A. 68.4
B. 62.2
C. 58
D. 27
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mnotageek

• Member Since Jul-2007 | Jul 19th, 2007

ok let us suppose 100 kg of fuel is being wasted.. if i use the A then 30 kg will be saved n 70 kg will be wasted. now if i bring in B it will save 40% of 70 n (70*0.6)=42 kg will be wasted. Now if i incorporate C then it will save 10%of 42 i.e..,(42*0.9) 37.8 kg will be wasted... so 100-37.8=62.2 kg will be saved.. so ans is 62.2%

#### mnotageek Profile Answers by mnotageek

• Jul 19th, 2007

ok let us suppose 100 kg of fuel is being wasted.. if i use the A then 30 kg will be saved n 70 kg will be wasted. now if i bring in B it will save 40% of 70 n (70*0.6)=42 kg will be wasted. Now if i incorporate C then it will save 10%of 42 i.e..,(42*0.9) 37.8 kg will be wasted... so 100-37.8=62.2 kg will be saved.. so ans is 62.2%

#### ramesh

• Sep 22nd, 2007

= (70/100)*(60/100)*(90/100)
= 0.378
=37.8 in%
=>100-37.8
=62.2

#### a.karthickeie Profile Answers by a.karthickeie

• Jul 21st, 2008

combination of three mechanism is
30+40+10=80/3
=26.666=27

#### sudipsinha123 Profile Answers by sudipsinha123

• Jul 13th, 2009

The Fuel economy efficiency for A,B,C will be 1/3,1/4 and 1/10 respectively

Hence the combined Fuel Economy efficiency will be (1/3+1/4+1/10)=41/60

in % form it will be (41/60)x100=68% approx.

#### Siddhubias Profile Answers by Siddhubias

• Apr 21st, 2010

Let each mechanism solution is 100 litre.

In "A" mechanism, wastage is (100-30)/100 = 70 %
In "B" mechanism, wastage is (100-40)/100 = 60 %
In "C" mechanism, wastage is (100-10)/100 = 90 %

If all are combined,total solution = 300 litres
Total wastage  = 220 litres
Total used fuel = 80 litres

So, wastage in 100 litres = 80/3 litres
% wastage = 26.6666.... %
= 27 % (approx)

#### Mudit

• Jan 24th, 2017

How can you apply efficiency on wasted fuel?

#### Anirudh Dayma

• Jul 11th, 2017

assume total =100 then 30% = 70, 40% reduction = 3/5 and 10% reduction = 9/10. Therefore total reduction = 70X(3/5)X(9/10) = 37.8 therefore ans = 100 - 37.8 = 62.2