The price of petrol is increased by 10%. By how much percent the consumption be reduced so that the expenditure remains the same?

• 9% using formulae [r/(100+r%)]*100
• 11 years agoHelpfull: Yes(14) No(5)
• lets assume initial 1 liter petrol cost=100
  10% increase=100+10/100*100=110(that is 1 liter petrol cost is increased)
  expenditure is same.that means we should buy the petrol only for 100 rupees.
  increased amount of petrol is rs.10. that means this rs.10 is the part of amount in rs.110
  now,
  we should find what is the percentage of rs.10 in rs.110(because if you remove this rs,10,then you will get the same expenditure)
  =10/110*100=9.09%
  so 9% of consumption should be reduced.
  
• 9 years agoHelpfull: Yes(9) No(0)
• 9% consumption has to be reduced.
  
  because (91/100)*110 = 100
  i.e 91 percent of (100 + 10) percent = 100 percent.
• 12 years agoHelpfull: Yes(3) No(19)
• 100/11 =9.09
  
• 8 years agoHelpfull: Yes(2) No(0)
• these questions are simple
  u can use this trick
  10% means 1/10 so reduce consumption by 1/10+1=1/11=9.09%
• 8 years agoHelpfull: Yes(1) No(0)
• Let the initial price of petrol be: Rs. x
  Let the initial consumption of petrol be : y
  price after 10% increase:x+(10x/100)=1.1x
  let z amount needs to be reduced.
  by questn:
  x*y=1.1*z*x*y
  =>z=1/1.1
  =>z=.9
  so,
  reduced amount=1-.9=.1
  hence,
  percentage reduction=10%
  
• 11 years agoHelpfull: Yes(0) No(21)
• 9+1/11
  the reduce factor is=10/11/*100
• 8 years agoHelpfull: Yes(0) No(2)
• by using the formula r/100+r%*100
  r=10
  10/100+10*100
  10/110*100
  100/110
  10/11
  9%
• 6 years agoHelpfull: Yes(0) No(0)
• E=P*C
  where E=expenditure
  P=price
  c=consumption
  
  when E=0(does not change means)
  E=p*c
  0=10-x-10X/100
  x=9.09%
• 6 years agoHelpfull: Yes(0) No(0)
• (10/110)*100=9.09%
• 6 years agoHelpfull: Yes(0) No(0)