how much more money will anna have when zachs investments are worth $900

Question

Anna and zach each have $600 to invest .Anna's investments earn a rate of 10.5% , and zach's investments earn a rate of 6.5% , approximately how much more money will anna have than zach when zachs investments are worth 900$

Answer 1

i = p · r · t, where i = interest, p = principal, r = rate, t = time

 

For Zach

900 = 600 · 0.065 · t

900 = 39 t

900/39 = t

 

For Anna

i = 600 · 0.105 · 900/39

i ≈ 1453.85

 

Anne earned approximately $553.86 more than Zach