Bunuel I would ask one thing if I can: in this kind of problem algebra (set up an equation) is faster than for instance backsolving in general, or always depends on you ??
It Always depends on you!
For this question i did in this way.
50000 - 10 % = 7500
Then commission for remaining amount will be 24000-7500=16500
Then amount which gives this 16500 as 10% should be 165000.
Therefore summing up 165000+50000 = 215000
This was the way i felt easy for me.
GMAT - Practice, Patience, Persistence
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