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# Earthworks question watch

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1. An embankment 7.5 m high has a side slope of 1 :3 on one side and 1 : 7 on the other. How much wider is the bottom of the embankment than its top?

Surely this would depend on the length of the top of the embankment? for instance if the top was 1m then it would be 75 times wider hower if it was 10m then it would only 7.5 times wider? any help would be great
2. (Original post by Danjones1uk)
An embankment 7.5 m high has a side slope of 1 :3 on one side and 1 : 7 on the other. How much wider is the bottom of the embankment than its top?

Surely this would depend on the length of the top of the embankment? for instance if the top was 1m then it would be 75 times wider hower if it was 10m then it would only 7.5 times wider? any help would be great
I think they're looking for how many metres wider is it, rather than how many times. The former question can be answered, but not the latter.
3. Thanks Ghostwalker, I initially thought the same. But how can I know this if I don't know wide the top is?
4. (Original post by Danjones1uk)
Thanks Ghostwalker, I initially thought the same. But how can I know this if I don't know wide the top is?
The width of the top doesn't come into it, since they're asking how much wider is the bottom than the top, i.e. what's the width of the sloping bits.

That's A+B in the diagram.
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5. Ah gotcha, I think....

Would it be something along the lines of

A = 3 x 7.5 = 22.5
B = 7 x 7.5 = 52.5

6. (Original post by Danjones1uk)
Ah gotcha, I think....

Would it be something along the lines of

A = 3 x 7.5 = 22.5
B = 7 x 7.5 = 52.5

That would be my thinking.
7. Thanks very much Ghostwalker. All makes sense now.

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