Amy had 20% more money than John. After she spent 50% of her money, she had $72 less than John. How much money had she left?
John has $X.
Amy had X + 0.2X = $1.2X.
1.2x/2 = x - 72,
0.6x = x - 72,
x - 0.6x = 72,
0.4x = 72,
X = $180. = John's Amt.
X - 72 = 180 - 72 = $108 = Amy,s bal.
To solve this problem, let's go step by step:
Let's assume the amount of money John had as "x" dollars.
Amy had 20% more money than John, which means she had (x + 20% of x) dollars.
Since 20% is the same as 0.2, Amy had (x + 0.2x) = 1.2x dollars.
After Amy spent 50% of her money, she had (1.2x - 50% of 1.2x) dollars.
Since 50% is the same as 0.5, Amy had (1.2x - 0.5 * 1.2x) = (1.2x - 0.6x) = 0.6x dollars left.
According to the problem, Amy had $72 less than John, so we can set up the equation:
0.6x = x - 72
Now, let's solve for x:
0.6x - x = -72
-0.4x = -72
x = -72 / -0.4
x = 180
Therefore, John had $180.
Now we can find how much money Amy had left:
Amy had 1.2x dollars initially, so she had 1.2 * 180 = $216.
After Amy spent 50% of her money, she had 0.6x dollars left, which is 0.6 * 180 = $108.
Therefore, Amy had $108 left.