Reply
Thu 28 Apr, 2005 03:13 pm
Ryan bought a certain number of plants for his garden. In the morning, he planted half of what he bought plus 10 plants. In the afternoon, he planted half of what was left plus 5 plants. Feeling tired, he left the rest until the next day, when he planted half of what was left. He then had 5 plants left that were in bad shape.
How many plants did he start with?
He started with 80 plants
He planted 50 in the morning, leaving 30
He planted 20 in the afternoon, leaving 10
The next day he planted 5, leaving 5
Is it OK to show the method?
Here's mine FWIW..............
Bought n plants.
Morning planting n/2 + 10
Remainder n - (n/2 + 10) = n/2-10 plants
Afternoon planting [(n/2 - 10) / 2] + 5 planted = n/4
Remainder [n/2 - 10] - n/4 = n/4 - 10
Next day planting [n/4 - 10] / 2 = n/8 -5
So total planting is [n/2 + 10] + n/4 + [n/8 - 5] = (7/8)n + 5
Also, total planting = n - 5 (since 5 left over)
(7/8)n + 5 = n - 5
Hence n = 80
The rest you can fill in by starting with 80 plants.
Stumble It!
Tweet This
Bookmark on Delicious
Share on Facebook
Share on MySpace