General Aptitude - Money and Sharing

Question

M men agree to purchase a gift for Rs. D. If three men drop out, how much more will each have to contribute towards the purchase of the gift?

• A. D/(M-3)
• B. MD/3
• C. M/(D-3)
• D. 3D/(M$^2$-3M)

Answer 1

M man agree to purchase a Gift for Rs. D.

Cost of gift Per man =$\frac{D}{M}$

 

After Drop  out 3 man cost of gift per man = $\frac{D}{M-3}$

Difference in contribution of gift per man =  $\frac{D}{M-3}$-  $\frac{D}{M}$

=D $(\frac{1}{M-3}$-  $\frac{1}{M})$

=$\frac{3D}{M^{2}-3M}$

 

Hence,Option(D) $\frac{3D}{M^{2}-3M}$ is the correct choice.

Comments

in last line some calculation mistake it should be 3d/m^2-3m

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How did you simplify D( (1/M) - (1/ ( M-3 ) ) ) Please explain.