# Question

Kai Yi and Isaac were given some money each. If Kai Yi spent \$25 and Isaac spent \$75 each, Kai Yi will still have \$2100 while Isaac spent all his money. If Kai Yi spent \$75 and Isaac spent \$25 each day, Kai Yi would still have \$900 while Isaac had spent all his money. How much money was given to each of them?

Scenario 1,
KY : Isaac => 25 : 75 , KY has \$2100 left

Scenario 2,
KY : Isaax => 75 : 25 , KY has \$900 left.

Both scenario, ISaac spent all his mnoney. Which also mean that’s the amount he has in the begining

We multiply 3 to scenario 2, so both scenario share common units. And that make sense coz in the end, Issac spent what he has in both scenario.

Scenario 2 now becomes,
KY : Isaac => 225 : 75, and KY has 900 left.

Now both scenario share common units, I can define KY money with two equation, one each from both scenario
KY = 25u + \$2100
KY = 225u + \$900

25u + 2100 = 225u + 900
200u = 1200
u = 6

KY was given = 25u + 2100 = \$2250 ###
Isaac was given = 75u = \$450 ###