Question

Kevin, Lyn and Mandy had a total of 1440 magazines. Kevin gave 1/3 of his magazines to Mandy. Lyn gave 2/5 of her magazines to Kevin. In the
end, Kevin had 334 magazines more than Lyn and Lyn had 332 magazines
less than Mandy. How many magazines did Mandy have at first?

Answer 1

let the number of mags for Kevin, Lyn and Mandy be
k, l, and m respectively

k + l + m = 1440 **
after the great magazine exchange:
Kevin has (2/3)k + (2/5)l
l has 3/5 l
Mandy has m + 1/3 k

"Kevin had 334 magazines more than Lyn"
---> (2/3)k + (2/5)l - (3/5)l = 334
(2/3)k - (1/5)l = 334
times 15
10k - 3l = 5010 ***

"Lyn had 332 magazines less than Mandy"
m + (1/3)k - (3/5)l = 332
times 15
15m + 5k - 9l = 4980 ****

You now have 3 equations in 3 unknown.
I solved them and go 3 reasonable answers

I assume you know how to solve this system, let me know what you get