February 10th, 2018, 11:01 AM  #1 
Newbie Joined: Jul 2015 From: N/A Posts: 14 Thanks: 0  Word problem
You deposit \$2000 in account A, which pays 2.25% annual interest compounded monthly. You deposit another \$2000 in Account B, which pays 3% annual interest compounded monthly. When is the sum of the balance in both accounts at least \$5000? Thank you in advance! Last edited by greg1313; February 10th, 2018 at 12:27 PM. 
February 10th, 2018, 01:06 PM  #2 
Global Moderator Joined: May 2007 Posts: 6,527 Thanks: 588 
after n months: account A 2000(1+.0225/12)^n account B 2000(1+.03/12)^n Find n when sum exceeds 5000. 
February 10th, 2018, 01:48 PM  #3 
Math Team Joined: Oct 2011 From: Ottawa Ontario, Canada Posts: 12,609 Thanks: 845 
u = (1 + .0225/12) v = (1 + .03/12) 2000(u^n) + 2000(v^n) = 5000 ; divide by 2000: u^n + v^n = 5/2 Brute solving: after 102 months: A = ~2421, B = ~2580, A + B = 5001 
February 12th, 2018, 07:08 AM  #4 
Newbie Joined: Jul 2015 From: N/A Posts: 14 Thanks: 0 
Mathman, Denis, Thank you! 
February 12th, 2018, 07:32 AM  #5 
Math Team Joined: Oct 2011 From: Ottawa Ontario, Canada Posts: 12,609 Thanks: 845 
I got you 5001 instead of 5000: you owe me a dollar!!


Tags 
problem, word 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Word problem  lookaway  Elementary Math  2  September 21st, 2017 08:02 PM 
word problem  nyuviolets  Algebra  3  July 25th, 2015 05:01 AM 
Word Problem  Ashley  Calculus  1  November 23rd, 2009 02:55 PM 
Word Problem  boognish  Elementary Math  2  November 6th, 2009 04:58 PM 
Word problem  hemidol  Calculus  2  June 1st, 2009 05:06 AM 