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john and nat were given some money. if john spends $50 and nat spends $100 each day, john would still have $2500 left
while nat would have spent all her money. if john spends $100 and nat spends $50 each day, john would still have $1000 left
while nat would have spent all her money. How much money john and nat were given each?
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Let J be the amount John had initially and let x be the number of days in the 1-st scenario.
Let N be the amount Nat had initially and let y be the number of days in the 2-nd scenario.
For the first scenario, we have these two equations
J = 50x + 2500, (1)
N = 100x. (2)
For the second scenario, we have these two equations
J = 100y + 1000, (3)
N = 50y. (4)
In all, we have 4 equations in 4 unknown J, N, x and y, so we have a chance to solve it.
From eq(2), express x = and substitute it into eq(1). You will have
J = 50*(N/100) + 2500, or J = (1/2)*N + 2500, or 2J - N = 5000 (5)
From eq(4), express y = and substitute it into eq(3). You will have
J = 100*(N/50) + 1000, or J = 2N + 1000, or J -2N = 1000 (6)
Thus, we reduced the problem to two equations in 2 unknowns
2J - N = 5000 (5)
J - 2N = 1000 (6)
From eq(6), express J = 2N + 1000 and substitute it into eq(5). You will get
2*(2N + 1000) - N = 5000,
which implies
4N + 2000 - N = 5000
3N = 5000 - 2000 = 3000
N = 3000/3 = 1000.
Then from eq(5)
2J = 5000 + 1000 = 6000
J = 6000/2 = 3000.
ANSWER. John had 3000; Nat had 1000.
Solved.