Question 826096: the coin collection was being sold. chloe bought half of the coins plus 5 more, then steve bought 5, then kirk bought 10 more than half of what was left, and then jesscia bought 25. leaving 10 unsold. how many coins where there orginally?
Found 2 solutions by Edwin McCravy, josmiceli:
Answer by Edwin McCravy(20064)   (Show Source):
You can put this solution on YOUR website! the coin collection was being sold. chloe bought half of the coins plus 5 more, then steve bought 5, then kirk bought 10 more than half of what was left, and then jesscia bought 25. leaving 10 unsold. how many coins where there orginally?
Show the movie backward, i.e. retrace the steps in reverse order.
Start with the 10 unsold ones.
Jessica bought 25. So before she came in, there were 10+25 or 35.
Suppose there were x coins before Kirk came in. He bought 1/2x + 10,
So x coins minus 1/2x+10 left the 35. So we have
x - (1/2x+10) = 35
x-1/2x-10 = 35
1/2x = 45
x = 90
So there were 90 coins before Kirk came in.
Steve bought 5, so there were 90+5 or 95 before Steve came in.
Suppose there were y coins before Chloe came in. She bought
half of the coins plus 5 more. So she bought 1/2y+5. So we have
the equation: y coins minus 1/2y+5 left the 95. So we have
y - (1/2y+5) = 95
y - 1/2y - 5 = 95
1/2y - 5 = 95
1/2y = 100
y = 200
So there were 200 coins before Chloe came in. That's the answer
Answer: 200 coins.
-----------------------------
Let's check it:
the coin collection contained 200 coins.
chloe bought half of the coins plus 5 more,
So she bought 100+5 or 105. That left 200-105 = 95 coins.
then steve bought 5.
That left 95-5 = 90 coins.
then kirk bought 10 more than half of what was left,
So kirk bought 45+10 or 55
That left 90-55 = 35
and then jessica bought 25.
So that left 35-25 = 10 coins
leaving 10 unsold.
That checks!
Edwin
Answer by josmiceli(19441)  (Show Source):
|
|
|
