Solve this mathematical problem, mentioning equations, and explaination?

Question

Lisa has twice of what jim has, if she gives him 300 $ he will be having 100 $ more than what she has, how much was with Lisa originally??

Answer 1

L = what Lisa has
J = what Jim has.

I am translating the problem.
"Lisa has twice what Jim has"...
L = 2J

"If she gives him 300 he will have 100 more than what she has"
J + 300 = 100 + (L - 300)

(L - 300) because she GAVE him 300.

Thus we have 2 equations.

L = 2J
J+ 300 = 100 + L - 300

Substitute 2J for L in the 2nd equation.

J + 300 = 100 + 2J - 300

Solve for J and you get J = 500. Then since L = 2J, L = 1000.

Check answer by checking that everything in the question is true, i.e. Lisa has twice what Jim has etc.

So final answer is $1,000.00. Make sure you put the units (dollars) to get full credit.

Answer 2

Lisa's money = L; Jim's money =J;
but L =2J (we are told that she has twice the amount Jim has)
Lisa gives Jim $300 and now has $300 less herself; of course Jim is $300 richer and now has J+300. Jim is $100 richer than Lisa so Lisa must have J+200. Lisa originally had 2J before she gave away $300. So J+200= 2J-300(she gave away $300)
therefor 2J-300-J-200=0 or J=500
Jim had $500 originally and Lisa originally had twice Jim's amount or $1000.

Answer 3

You start off by knowing two things are true

Lisa = 2 x Jim
(Jim + 300) - (Lisa - 300) = 100

You can combine the two by replacing Lisa with 2 x Jim

(Jim + 300) - (2 x Jim - 300) = 100

Then take 300 from the 2nd part of the equation and add it to the 1st part

(Jim + 600) - (2 x Jim) = 100

rearrange a bit and you're left with

Jim + 600 - Jim - Jim = 100

You can get rid of a Jim and a -Jim leaving you with

600 - Jim = 100

So Jim equals 500

Lisa had twice what Jim had, so that' s $1,000

And to test it out
Lisa had $1,000, Jim had $500
Now Lisa has $700, Jim has $800

Problem solved

Answer 4

Let Jim have X so Lisa has 2X
Lisa gives away 300 so now has 2X - 300 and
Jim now has X + 300
But Jim has 100 more than Lisa so:-
X + 300 = (2X - 300) + 100
X + 300 = 2X - 200
X + 500 = 2X
500 = X so Lisa had $1000 originally.

Answer 5

l =2j if l =money of Lisa, j money of Jim

and l-100= j+300 or l=j+200 and j+200=2j

so j=200 l=400

it works since l giving 300 to jim they will have l=100 j=300

Answer 6

suppose lisa has l$ and Jim has j %
then from first condition l=2j
and from 2nd condition l-300=(j+300) -100
l-j=500
and l-2j=0
now solving above j=500
l=1000
so lisa has 1000 and james has 500

Answer 7

Two plus two equals six.