
Richmond Y. answered 05/31/19
Patient Math Tutor for all ages
Ebola,
L = number of beers Laura started with
A = number of beers Anton started with
T = number of beers Tommy started with
first Laura gives 1/4 of her beers to Anton, that means Laura is left with 3/4 of what she started with
Laura = 3/4 L
Anton = 1/4 L + A
Tommy = T
After that Anton gives 1/2 of his beers to Tommy which leaves Anton with only 1/2 left
Laura = 3/4 L
Anton = 1/2(1/4 L + A)
Tommy = T + 1/2(1/4 L + A)
and Tommy gives 1/3 of his beers back to Laura which leaves Tommy with only 2/3 left
Laura = 3/4 L + 1/3(T + 1/2(1/4 L + A))
Anton = 1/2(1/4 L + A)
Tommy = 2/3(T + 1/2(1/4 L + A))
After this they have equally 18 beers per person
Laura = 3/4 L + 1/3(T + 1/2(1/4 L + A)) = 3/4 L + 1/3(T + 1/8 L + 1/2 A) = 3/4 L + 1/3 T + 1/24 L + 1/6 A= 18
19/24 L + 1/6 A + 1/3 T = 18
Anton = 1/2(1/4 L + A) = 18
Tommy = 2/3(T + 1/2(1/4 L + A)) = 2/3(T + 1/8 L + 1/2 A) = 2/3 T + 1/12 L + 1/3 A= 18
Now we simplify and substitute. I usually like to start with the simplest equation
1/2(1/4 L + A) = 18
1/8 L + 1/2 A = 18
1/2 A = 18 - 1/8 L
A = 36 - 1/4 L
Now substitute A in one of the other 2 equations
2/3 T + 1/12 L + 1/3 A= 18
2/3 T + 1/12 L + 1/3(36 - 1/4 L) = 18
2/3 T + 1/12 L + 12 - 1/12 L = 18
2/3 T + 12 = 18
2/3 T = 6
T = 9
Substitute T = 9 and A = 36 - 1/4 L into the first equation
19/24 L + 1/6 A + 1/3 T = 18
19/24 L + 1/6(36 - 1/4 L) + 1/3 * 9 = 18
19/24 L + 6 - 1/24 L + 3 = 18
19/24 L - 1/24 + 9 = 18
18/24 L = 9
L = 12
Lastly substitute L = 12 into the second equation.
A = 36 - 1/4 L
A = 36 - 1/4 * 12
A = 36 - 3
A = 33
Verify that the sum of L, A, T equals 54
L = 12, A = 33, T = 9
L + A + T = 54
12 + 33 + 9 = 54
54 = 54
Answer:
Laura originally had 12 beers
Anton originally had 33 beers
Tommy originally had 9 beers
I hope this helps.
Please feel free to reach out to me for any clarification.
Thanks,
Richmond