Question 973330
I'll show you how to transform your answer into the book's answer



{{{300(1-(1/2)^10)/(1-1/2)}}}  



{{{300(1-(1^10)/(2^10))/(1-1/2)}}}  



{{{300(1-(1)/(2^10))/(1-1/2)}}}  



{{{300(1*((2^10)/(2^10))-(1)/(2^10))/(1-1/2)}}}  



{{{300((2^10)/(2^10)-(1)/(2^10))/(2/2-1/2)}}}  



{{{300((2^10-1)/(2^10))/((2-1)/2)}}}  



{{{300((2^10-1)/(2^10))/(1/2)}}}  



{{{300((2^10-1)/(2^10))*(2/1)}}}  



{{{300((2^10-1)/(2^10))*((2^1)/1)}}}  



{{{300((2^10-1)/(2^9))}}}  



{{{75*4((2^10-1)/(2^9))}}}  



{{{75*2^2*((2^10-1)/(2^9))}}}  



{{{75*((2^10-1)/(2^7))}}}  



So that shows how your answer is equivalent to the book's answer. The book's answer is slightly simpler though.