GMAT Problem Solving (PS) | Re: Andrew borrows equal sums of money under simple interest at 5% and 4%

let the amount borrowed in each case be x and time be t years
In case of 5% interest rate time would be 6 months less: (x*5*(t-0.5))/100 +x =1100
In case of 4% interest : (x*4*t)/100 +x=1100
=>5xt+2.5x=4xt
=>t=2.5
(4xt/100)+x=1100
substituting value of t
10x/100+x=1100
11x/10=1100
x=1000
total sum borrowed= x at 4% and x at 5% = 2x =2000
hence answer should be D

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