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# Gruber's Math Workbook Help

Registered User Posts: 8 New Member
edited November 2012
Does anyone have Gruber's Math Workbook that can help me understand the problem on page 268.

((1/2)(AB)h)/((1/2)(AB)h)=1/3

Why is the second AB not AD since its the base of the whole triangle? And where did the 1/3 come from?
Post edited by matt110029 on

## Replies to: Gruber's Math Workbook Help

• Registered User Posts: 8 New Member
By the way, I understand why it's 1/3 because the lines trisect the whole triangle in three equal parts which mean the area of one part is a third of the whole, but I want to understand it the way they did it in case I encounter more complex problems.
• Registered User Posts: 346 Member
The second.. what?
• Registered User Posts: 8 New Member
I mean't the bottom of the fraction.
• Registered User Posts: 346 Member
Oh no you're right; it should be AD.

Otherwise the answer would be 1. Which would be wrong.
x/x=1

Grubers has tons of mistakes.
• Registered User Posts: 8 New Member
Thanks! I thought I was missing something, but apparently not. This would've saved me much more time if I knew that earlier.
• Registered User Posts: 8 New Member
Wait, I don't think it was a mistake because he talks about how the AB cancels out. But, I just don't understand where the equation came from. Anyone else have Gruber's Math Workbook that can help?
This discussion has been closed.