How to solve this question ? (1 Viewer)

[fabl]

A give way sign with shape of an equilateral triangle has side length of 87 cm. The sigh is attached in two places to a metal pole.

How far from the top of the sign should the holes be drilled if the top hole divides the vertical height of the sign in the ratio 1:9 and the bottom in the ratio 8:9

I have solved the first part "1:9 ratio" and got the answer of 7.53 cm but having trouble with the "8:9" ratio?

 

[braintic]

A give way sign with shape of an equilateral triangle has side length of 87 cm. The sigh is attached in two places to a metal pole.

How far from the top of the sign should the holes be drilled if the top hole divides the vertical height of the sign in the ratio 1:9 and the bottom in the ratio 8:9

I have solved the first part "1:9 ratio" and got the answer of 7.53 cm but having trouble with the "8:9" ratio?

Find the vertical height of the sign [(87/2) sin60], and from this subtract the 7.53.

 

[SnivysTrainer]

Find the vertical height of the sign [(87/2) sin60], and from this subtract the 7.53.

Wouldn't that make the second ratio 9:1 though? The ratio of 1:9 has 10 parts, whereas the ratio of 8:9 has 17. I could be mistaken, but the way I did it was to say that 17 parts = [(87/2)sin60] so 1 part = [(87/2)sin60]/17. Therefore, 8 parts = [(87/2)sin60]/17 x 8. I think that's right, however I could very easily be mistaken.

 

[braintic]

Wouldn't that make the second ratio 9:1 though? The ratio of 1:9 has 10 parts, whereas the ratio of 8:9 has 17. I could be mistaken, but the way I did it was to say that 17 parts = [(87/2)sin60] so 1 part = [(87/2)sin60]/17. Therefore, 8 parts = [(87/2)sin60]/17 x 8. I think that's right, however I could very easily be mistaken.

Sorry, I didn't read the question carefully enough.

 

[SnivysTrainer]

Sorry, I didn't read the question carefully enough.

No worries. It happens to the best of us, and I am definitely nowhere near the best. ^^

 

[fabl]

Thanks all for helping out, the questions for final part has the answer of 35.46 cm, so still thinking about it .

 

[fabl]

oh yep just figured it out, its 75.34/17 x 8 which makes the 35.46 answer D