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Barbara invests $2,400 in the National Bank at 5%. How much additiona
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05 Mar 2018, 21:39
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Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment? (A) $2,400 (B) $3,600 (C) $1,000 (D) $3,000 (E) $1,200
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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05 Mar 2018, 21:43
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200 4. Percents and Iterest For more check: ALL YOU NEED FOR QUANT ! ! !Ultimate GMAT Quantitative MegathreadHope it helps.
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Barbara invests $2,400 in the National Bank at 5%. How much additiona
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05 Mar 2018, 23:40
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200 If the interest earned is represented as follows 58 6 21 the investment must be done in the ratio 2:1 Therefore, we would need to invest $1200(Option E) at a rate of 8% so that the total annual income is 6% Alternate approachLet x be the amount invested at 8% \(0.05*2400 + 0.08*x = 0.06(2400 + x)\) > \(120 + 0.08x = 144 + 0.06x\) > \(0.02x = 24\) > \(x = \frac{2400}{2} = $1200\)
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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06 Mar 2018, 01:59
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200 We need to have the equation as follows. Additional money=x Therefore, (6/100)*x+144=120+(8/100)*x Solving for x, x=1200 Answer E



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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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08 Mar 2018, 11:37
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200 We can let x = the amount of money invested at 8%, making her entire investment equal to (2,400 + x). We can create the following equation: 0.05(2,400) + 0.08x = 0.06(2,400 + x) 120 + 0.08x = 144 + 0.06x 0.02x = 24 2x = 2400 x = 1,200 Answer: E
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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04 Oct 2018, 19:25
Hi All, We're told that Barbara invests $2400 in the National Bank at 5%. We're asked how much additional money she must invest at 8% so that the TOTAL annual income will be equal to 6% of her TOTAL investment. This question can be solved in a couple of different ways, including by TESTing THE ANSWERS. To start, the $2400 invested at 5% would earn ($2400)(.05) = $120. Since Barbara invested $2400 at 5%, IF she were to invest another $2400 at 7%, then the average return for the total investment would be exactly 6% (since the EQUAL investments at 5% and 7% would 'average out' to 6%. Here though, she's investing money at 8%  which means that she would NOT need $2400 invested there (she would need LESS than that, since the investment is at a higher rate). Thus, the answers are narrowed down to either $1000 or $1200. It's interesting that one of the two options is EXACTLY HALF of 2400.... Let's TEST Answer E = $1200 IF... $1200 were invested at 8%, then that investments would earn (1200)(.08) = $96 the total money invested would equal $2400 + $1200 = $3600 the total return on the investment would be $120 + $96 = $216 1% of $3600 = $36 6% of $3600 = $216 This is an exact match for what we were told, so this MUST be the answer. Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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27 Jan 2019, 06:44
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200
Let´s use ALLIGATION, one powerful technique covered in our course! \(? = x\) \({{2400} \over {2400 + x}} = {{8  6} \over {8  5}} = {{2 \cdot 1200} \over {3 \cdot 1200}}\,\,\,\,\, \Rightarrow \,\,\,\,\,? = x = 3 \cdot 1200  2400 = 1200\) We follow the notations and rationale taught in the GMATH method. Regards, Fabio.
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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27 Jan 2019, 07:13
Bunuel wrote: Barbara invests $2,400 in the National Bank at 5%. How much additional money must she invest at 8% so that the total annual income will be equal to 6% of her entire investment?
(A) $2,400
(B) $3,600
(C) $1,000
(D) $3,000
(E) $1,200 Barbara invests $2400 in the National Bank at 5%. So, her annual income for this investment = 5% of $2400 = $120Let x = the additional money Barbara must invest at 8% So, her annual income for this investment = 8% of x = 0.08xSo, Barbara's TOTAL annual income = $120 + 0.08xWe want the TOTAL annual income to be equal to 6% of her entire investment. The TOTAL amount invested = $2400 + x So, we want her TOTAL annual income to equal 6% of ($2400 + x) In other words, we want: Barbara's TOTAL annual income = 0.06($2400 + x)We now have the equation: $120 + 0.08x = 0.06($2400 + x)Expand right side: 120 + 0.08x = 144 + 0.06x Subtract 0.06x from both sides to get: 120 + 0.02x = 144 Subtract 120 from both sides to get: 0.02x = 24 Solve: x = 24/0.02 = 2400/2 = 1200 Answer: A Cheers, Brent
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Re: Barbara invests $2,400 in the National Bank at 5%. How much additiona
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