A) Rs.300
B) Rs.400
C) Rs.500
D) Rs.600
Correct Answer: B
Solution :
Let no. of students appeared in exam = x Now, \[Gain\text{ }%=\frac{Gain\times 100}{C.P.},\]pass in English (some may fail in Maths) and \[Loss%=\frac{Loss\times 100}{C.P.}\] pass in Maths (some may fail in Eng) Since, \[S.P.=\frac{100+gain%}{100}\times C.P.\] students passed in both subjects Hence, no. of students passed only in English \[S.P.=\frac{100-loss%}{100}\times C.P.\] and no. of students passed only in Maths \[C.P.=\frac{100}{100+gain%}\times S.P.\] Now, students passed in both subjects + passed only 3 in maths + passed only in English \[C.P.=\frac{100}{100-loss%}\times S.P.\] Now, 40 students failed in both subjects. \[=\frac{{{x}^{2}}}{100}%,\] Total students = (passed + failed) students\[=x\] \[\frac{{{x}^{2}}}{100}%,\] \[Discount%=\frac{Discount}{M.P.}\times 100\] \[\text{-}\frac{\text{Discount }\!\!%\!\!\text{ }\!\!\times\!\!\text{ M}\text{.P}\text{.}}{\text{100}}\] \[S.P.=M.P.\times \left\{ 1-\frac{Discount%}{100} \right\}\] \[\text{S}\text{.P}\text{.=M}\text{.P}\text{. }\!\!\times\!\!\text{ }\left\{ \text{1-}\frac{\text{Discount }\!\!%\!\!\text{ }}{\text{100}} \right\}\] \[\text{S}\text{.P}\text{.=M}\text{.P}\text{. }\!\!\times\!\!\text{ }\left\{ \frac{\text{100 - Discount }\!\!%\!\!\text{ }}{\text{100}} \right\}\]\[M.P.=\frac{100\times S.P.}{100-Discount%}\] \[\left( x+y-\frac{xy}{100} \right)%\]You need to login to perform this action.
You will be redirected in
3 sec