rashmi.kaushal wrote:Sally has a gold credit card with a certain spending limit, and a platinum card with twice the spending limit of the gold card. Currently, she has a balance on her gold card that is 1/3 of the spending limit on that card, and she has a balance on her platinum card that is 1/5 of the spending limit on that card. If Sally transfers the entire balance on her gold card to her platinum card, what portion of her limit on the platinum card will remain unspent?

11/30
29/60
17/30
19/30
11/15
OA later

Hey,

Lets say $150 is the limit on gold card, then the limit on platinum is $300.

1/3 of gold has been used so $50 balance and $100 remaining.
1/5 of platinum has been used so $60 and the remaining balance is $240.

now all we need to do is transfer the balance from gold to platinum.

$240(remaining from platinum) - 50 (from gold) = $190.

190/300 = 19/30.

I hope that helps!

pick numbers. when i scan a problem like this and spot 2 fractions, i immediately think "choose common denominator"... since we're dealing in dollars, i thought it best to work with $150, not too small not to big in terms of manipulating.

S = Spending limit
B= Balance

GOLD PLATIZZY
S=$150 2S =300
B= 1/3S= 50 B=1/5(2S) = 60

Transfer Gold to Platizzy gives you a new balance of $110, and "unspent" of $190 ($300 - $110).

So the answer should be D. 190/300 = 19/30.

I was able to solve the problem on my own, but i wasn't able to solve it the other way around. where the gold card = x and the platinum card = 2x. can any explain the process for solving the problem in that manner?

sdotcruz wrote:I was able to solve the problem on my own, but i wasn't able to solve it the other way around. where the gold card = x and the platinum card = 2x. can any explain the process for solving the problem in that manner?

assume that Gold card limit is x . balance is x/3.
platinum card limit is 2x. balance is 2x/5
after balance transfer total balance on the platinum card is 2x/5+x/3 = 11x/15.

unspent amount on platimum card = total limit(2x)-balance(11x/15) = 19x/15

fraction = unspent/total = (19x/15)/2x = 19/30.