Huimei spent 3 8 of her money on stationary and 1 2 of the money left on a pen. She has $2.50 left. How much money did she have at first left?
Let M be the money that Huimei had at first.
Huimei spent 3/8*M on stationary.
She had (5/8)*M left.
Huimei spent 1/2*(5/8)*M = 5/16*M on a pen.
She had (5/8)*(1/2)*M = 5/16*M left.
Huimei has 2.50 = 5/16*M left.
Therefore, M = 2.50/(5/16) = 2.50*16/5 = 10.00
At first, Huimei had $10. Answer: \boxed{10}.
Let's assume Huimei had x dollars initially.
Step 1: Money spent on stationary = 3/8 * x
Step 2: Money left after buying stationary = x - (3/8 * x) = (8/8 - 3/8) * x = 5/8 * x
Step 3: Money spent on a pen = 1/2 * (5/8 * x) = (1/2) * (5/8) * x = 5/16 * x
Now, we know that she has $2.50 left, which is equal to 250 cents.
Step 4: Money left after buying a pen = (5/8 * x) - (5/16 * x) = (10/16 * x) - (5/16 * x) = 5/16 * x
Given that money left = $2.50 = 250 cents, we can set up an equation:
5/16 * x = 250
To solve for x, we can multiply both sides of the equation by 16/5:
x = (250 * 16/5)
x = (50 * 16)
x = 800
Therefore, Huimei initially had $800.
To find out how much money Huimei had initially, we need to work backwards from the information given in the question.
Let's start by figuring out how much money she had left after spending 3/8 of her money on stationary. Since she has $2.50 left, we know that this amount represents 5/8 of her original money. So, we can set up an equation:
(5/8) * initial amount = $2.50
To solve for the initial amount, we need to isolate it on one side of the equation. We can do this by multiplying both sides of the equation by (8/5), the reciprocal of (5/8):
initial amount = $2.50 * (8/5)
Simplifying the equation gives:
initial amount = $4.00
Therefore, Huimei had $4.00 initially.