Question 621264
Let x=original price SO number bought=2000/x
New price=x-10 So number bought= 2000/X-10)   This is 10 more than before
So 2000/(x-10)-2000/x =10
Muliply throughout by x(x-10)getting 2000x-2000(x-10)= 10x(x-10)
Divide throughout by and rearrange x^2-10x-2000=0 (x-50)(x+40)=0 So x=50
That is original price was 50  So number bought was 2000/50=40