Andre has $30, and Erin has $14. Andre is saving $5 per day, and Erin is saving $9 per day. After how many days will Andre and Erin have the same amount of money?
Let's call the number of days it takes for Andre and Erin to have the same amount of money "x".
After x days, Andre will have saved a total of:
$30 + ($5/day * x)
After x days, Erin will have saved a total of:
$14 + ($9/day * x)
We want to find the value of x that makes these two expressions equal:
$30 + ($5/day * x) = $14 + ($9/day * x)
We can start solving for x by subtracting $14 and $5/day from both sides:
$16 = ($4/day * x)
Now we can solve for x by dividing both sides by $4/day:
x = 4 * $16/day
x = 64/4
x = 16
Therefore, it will take 16 days for Andre and Erin to have the same amount of money.
To find out after how many days Andre and Erin will have the same amount of money, we need to compare their savings rates.
Andre is saving $5 per day, and Erin is saving $9 per day.
Let's calculate how many days it will take for their savings to be equal:
Amount Andre saves per day = $5
Amount Erin saves per day = $9
The difference in their savings per day is:
$9 - $5 = $4
To determine the number of days needed for their savings to be equal, we divide the difference in their total savings by the difference in their savings per day:
Amount Andre has = $30
Amount Erin has = $14
Difference in their total savings = $30 - $14 = $16
Number of days needed = Difference in total savings / Difference in savings per day
Number of days needed = $16 / $4 = 4 days
So, it will take 4 days for Andre and Erin to have the same amount of money.