Friday

August 28, 2015
Posted by **Katherine** on Thursday, September 19, 2013 at 6:15pm.

- Math -
**Steve**, Thursday, September 19, 2013 at 6:58pmLater tree count m:o = 3:11

So, if there were 3x maples and 11x oaks, x=12. There were

36 maples and 132 oaks.

that makes 168 trees in all

Original tree count: m:o = 9:5

So, there were 9x maples and 5x oaks, and

9x+5x = 168

x = 12

There were 108 maples and 60 oaks.

The maples fell from 108 to 36, for a difference of 72

- Math -
**Shayla**, Tuesday, September 24, 2013 at 9:49pm60 and 108

- Math -
**Demari Boyd**, Thursday, August 28, 2014 at 7:58pmthe answer i came up with is 6480

- Math -
**Michelle**, Tuesday, September 16, 2014 at 2:57amSteve has the correct solution, but the method used in the Common Core lesson involves proportions.

The current ratio of maple to oak trees is 3:11 and there are now 132 oak trees.

3 maple trees X maple trees

------------- = ---------------

11 oak trees 132 oak trees

using cross multiplication,

11x = 396 divide both sides by 11 to get

x = 36

So now there are 36 maple trees.

Because there were new trees planted after the bugs to make the same number f trees before and after the bugs, we know there are 36 + 132 = 168 total trees. We use this total in the other proportion to solve.

Before the bugs, we know the ratio was 9 maple trees to 5 oak trees. However, this next proportion needs to find the number of maple trees using the total number of trees. So we add the trees in this ratio for a total number of trees to use in this ratio. 9 + 5 = 14. So the ratio of maple tree to the total number of trees is 9:14. This is used in the second proportion.

9 maple trees X maple trees

------------- = ---------------

14 total trees 168 total trees

Using cross multiplication, we get

14x = (9)(168)

14x = 1512 dividing both sides by 14,

x = 108

So there were 108 maple trees before bugs.

From the earlier proportion, there are now 36 maple trees.

So there were 108 - 36 = 72 more maple trees before the bugs.

This is not what I would consider a 6th grade math problem, especially considering I found 2 adults who got confused by this process, so I have no problems with posting the complete solution here.

- Math -
**helen**, Monday, October 6, 2014 at 8:53pmsooo you want to add 12plus12 and that's how you get your answer.do your homework by self not with help haha

- Math -
**Riverhead Charter**, Monday, October 6, 2014 at 9:00pmdon't make me tell you the wrong answers UGLY!! what is wrong with you guys add everything together then divide it by 2 because 2 is a great number

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**Helen**, Monday, October 6, 2014 at 9:04pmim so sorry this is Helen Gonzalez please forgive me im so sorry don't tell my teachers cause if you do you will get hurt bad

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**Helen**, Monday, October 6, 2014 at 9:05pmlove roque'

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- Math -
**Helen**, Monday, October 6, 2014 at 9:07pmI poop my pants everyday