My Solutions (Core; Graphs; Networks; Matrices)

[shmootz]

I OBJECT:

Question 8 in Networks:

If you forward and backward scan this network, the minimum completion time is 18 | 18. It says the duration of each activity can be reduced by one hour.
To complete this project in 16 hours, the minimum number of activities that must be reduced by one hour each is:

If the completion time is 18, you need to reduce it by 2 hours. If you reduce 2 activities by one hour each (as that's the limit) shouldn't the answer be B?

This is given that I've forward scanned and backward scanned correctly, which I believe I have. If I haven't, please subject me to the highest form of shame.

Sorry, but it should be C.
There are two critical paths : A-F-H and B-C-F-H (18 hours each), as well as the path A-E-G (17 hours).
To reduce the critical paths to 16, H must be reduced, and reducing A and B then brings all the paths over 16 hours down to 16 hours. (hard to explain sorry!)

I may be wrong but just trying to understand... Why can't F and H each be crashed by one hour? That would mean your shortest path is 7+4+5 = 16, by only crashing two (answer B)?

[oneialex]

The last question in business maths is C, not A

I got the same thing. A doesn't show that the loan was fully repayed (as implied in the question), while C does.

[StumbleBum]

The last question in business maths is C, not A

No, its A. If you put all the information into the calculator, then you end up with a final value of about $2. As this is not 0, it can't be C.

the question states that "he planed to repay the loan fully", however in reality he doesn't fully pay it off.

[djsandals]

nooo whaat D:
for graphs and relations - question 8
isnt it A??? i have a formula that i got from my teacher that says
"for each x there is at least 5y" and then its 2y<(including arrow)x

Yeh I'm probably wrong but it's the only question I got wrong that I didn't understand

[julie9300]

Question 5 networks, you can test it on the second diagram (the pentagon sorta diagram) and an Euler circuit exists. So either way, the answer can't be 0.

[michelleeee]

nooo whaat D:
for graphs and relations - question 8
isnt it A??? i have a formula that i got from my teacher that says
"for each x there is at least 5y" and then its 2y<(including arrow)x

Yeh I'm probably wrong but it's the only question I got wrong that I didn't understand

ah im so silly!
i meant isnt q8 suppose to be B??
i got B too D: i hope thats right.... sighs
i made so many silly mistakes no more 100% T^T

[mooimachicken]

The last question in business maths is C, not A

No, its A. If you put all the information into the calculator, then you end up with a final value of about $2. As this is not 0, it can't be C.

the question states that "he planed to repay the loan fully", however in reality he doesn't fully pay it off.

um, where'd you get the final value of $2 from?

[oppalovesme]

I OBJECT:

Question 8 in Networks:

If you forward and backward scan this network, the minimum completion time is 18 | 18. It says the duration of each activity can be reduced by one hour.
To complete this project in 16 hours, the minimum number of activities that must be reduced by one hour each is:

If the completion time is 18, you need to reduce it by 2 hours. If you reduce 2 activities by one hour each (as that's the limit) shouldn't the answer be B?

This is given that I've forward scanned and backward scanned correctly, which I believe I have. If I haven't, please subject me to the highest form of shame.

Sorry, but it should be C.
There are two critical paths : A-F-H and B-C-F-H (18 hours each), as well as the path A-E-G (17 hours).
To reduce the critical paths to 16, H must be reduced, and reducing A and B then brings all the paths over 16 hours down to 16 hours. (hard to explain sorry!)

I may be wrong but just trying to understand... Why can't F and H each be crashed by one hour? That would mean your shortest path is 7+4+5 = 16, by only crashing two (answer B)?

You're right, that would bring both critical paths to 16, but a new critical path is then formed (A-E-G), which is 17. You must then crash one of those events to make 16.

[julie9300]

I OBJECT:

Question 8 in Networks:

If you forward and backward scan this network, the minimum completion time is 18 | 18. It says the duration of each activity can be reduced by one hour.
To complete this project in 16 hours, the minimum number of activities that must be reduced by one hour each is:

If the completion time is 18, you need to reduce it by 2 hours. If you reduce 2 activities by one hour each (as that's the limit) shouldn't the answer be B?

This is given that I've forward scanned and backward scanned correctly, which I believe I have. If I haven't, please subject me to the highest form of shame.

Sorry, but it should be C.
There are two critical paths : A-F-H and B-C-F-H (18 hours each), as well as the path A-E-G (17 hours).
To reduce the critical paths to 16, H must be reduced, and reducing A and B then brings all the paths over 16 hours down to 16 hours. (hard to explain sorry!)

I may be wrong but just trying to understand... Why can't F and H each be crashed by one hour? That would mean your shortest path is 7+4+5 = 16, by only crashing two (answer B)?

The critical path would have then been BCEG I think which has a completion time of 17.

[Yendall]

I OBJECT:

Question 8 in Networks:

If you forward and backward scan this network, the minimum completion time is 18 | 18. It says the duration of each activity can be reduced by one hour.
To complete this project in 16 hours, the minimum number of activities that must be reduced by one hour each is:

If the completion time is 18, you need to reduce it by 2 hours. If you reduce 2 activities by one hour each (as that's the limit) shouldn't the answer be B?

This is given that I've forward scanned and backward scanned correctly, which I believe I have. If I haven't, please subject me to the highest form of shame.

Sorry, but it should be C.
There are two critical paths : A-F-H and B-C-F-H (18 hours each), as well as the path A-E-G (17 hours).
To reduce the critical paths to 16, H must be reduced, and reducing A and B then brings all the paths over 16 hours down to 16 hours. (hard to explain sorry!)

I may be wrong but just trying to understand... Why can't F and H each be crashed by one hour? That would mean your shortest path is 7+4+5 = 16, by only crashing two (answer B)?

Exactly what I thought. As long as they are on either critical path it shouldn't matter should it?

[djsandals]

nooo whaat D:
for graphs and relations - question 8
isnt it A??? i have a formula that i got from my teacher that says
"for each x there is at least 5y" and then its 2y<(including arrow)x

Yeh I'm probably wrong but it's the only question I got wrong that I didn't understand

ah im so silly!
i meant isnt q8 suppose to be B??
i got B too D: i hope thats right.... sighs
i made so many silly mistakes no more 100% T^T

Yeah I was thinking about that question for like 5 minutes....somebody clarify!

[StumbleBum]

The last question in business maths is C, not A

No, its A. If you put all the information into the calculator, then you end up with a final value of about $2. As this is not 0, it can't be C.

the question states that "he planed to repay the loan fully", however in reality he doesn't fully pay it off.

um, where'd you get the final value of $2 from?

Put all the information into the calculator...
EDIT: Oh yeh, you can just make up information from what has been given, and then you change it to suit the new problem were he forgets to pay for one month and you end up with something that isnt 0

[Will T]

Question 5 networks, you can test it on the second diagram (the pentagon sorta diagram) and an Euler circuit exists. So either way, the answer can't be 0.

I see now. I have found a multitude of Eulerian circuits for the pentagon-shaped complete graph. I will try a similar process for the heptagon and nonagon. This means the range of possible answers is now 1-3 so alternatives B, C or D could be correct at the moment.

[Jezza]

nooo whaat D:
for graphs and relations - question 8
isnt it A??? i have a formula that i got from my teacher that says
"for each x there is at least 5y" and then its 2y<(including arrow)x

Yeh I'm probably wrong but it's the only question I got wrong that I didn't understand

ah im so silly!
i meant isnt q8 suppose to be B??
i got B too D: i hope thats right.... sighs
i made so many silly mistakes no more 100% T^T

Yeah I was thinking about that question for like 5 minutes....somebody clarify!

I thought it was A???

[shmootz]

I OBJECT:

Question 8 in Networks:

If you forward and backward scan this network, the minimum completion time is 18 | 18. It says the duration of each activity can be reduced by one hour.
To complete this project in 16 hours, the minimum number of activities that must be reduced by one hour each is:

If the completion time is 18, you need to reduce it by 2 hours. If you reduce 2 activities by one hour each (as that's the limit) shouldn't the answer be B?

This is given that I've forward scanned and backward scanned correctly, which I believe I have. If I haven't, please subject me to the highest form of shame.

Sorry, but it should be C.
There are two critical paths : A-F-H and B-C-F-H (18 hours each), as well as the path A-E-G (17 hours).
To reduce the critical paths to 16, H must be reduced, and reducing A and B then brings all the paths over 16 hours down to 16 hours. (hard to explain sorry!)

I may be wrong but just trying to understand... Why can't F and H each be crashed by one hour? That would mean your shortest path is 7+4+5 = 16, by only crashing two (answer B)?

You're right, that would bring both critical paths to 16, but a new critical path is then formed (A-E-G), which is 17. You must then crash one of those events to make 16.

Thank you! That's very helpful