A) \[25\frac{4}{7}%\]
B) \[26\frac{4}{7}%\]
C) \[27\frac{4}{7}%\]
D) \[28\frac{4}{7}%\]
Correct Answer: D
Solution :
(d): Let him consume 'x' kg previously Previous price = C Rs/kg \[\Rightarrow \text{cost}=xC\] New price = 1.4C Rs/kg. Let new consumption decrease by p%. \[\Rightarrow New\text{ }consumption=\frac{x(100-p)}{100}kg\] \[\therefore New\,cost=\frac{x\left( 100-p \right)}{100}\times \left( 1.4C \right)\] \[\therefore \frac{x\left( 100-p \right)}{100}\times \left( 1.4C \right)=xC\] \[\Rightarrow 1.4(100-p)=100\] \[\Rightarrow 140-1.4=100\] \[\Rightarrow 40=1.4p\] \[\Rightarrow p=\frac{40}{1.4}=\frac{40\times 5}{7}=\frac{200}{7}=28\frac{4}{7}%\]You need to login to perform this action.
You will be redirected in
3 sec