Tutor MathsGuru: Ask me for your burning Maths questions!
-
Dharma:
When the train emerges entirely from the tunnel of length L(tunnel) in 2 minutes, the distance travelled by the train will be the sum of the length of tunnel L(tunnel) and length of the train, L(train)
I was told verally that it is 60km! i was wondering how can the train be so long! hahahanettie:
[quote=\"Dharma\"]
Is the length of the train 60km or 60m?
L(tunnel) + L(train) = Speed of train (72km/h) x Time taken (2 mins/60 = 1/30hrs)
L (tunnel ) = 72/30 km – 60 km = 2.4km – 60km [ IMPOSSIBLE!!!!]
The length of train is likely to be 60m
L(tunnel) = 2.4km – 0.06km = 2.34km[/quote]Hi nettie,
Your question is similar to http://www.wendykoh.com/08/primary6-scgssa2-maths.pdf and that question was posted by http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=840 on Thu Sep 24, 2009 3:46 pm and the correct method used to solve this problem sum was confirmed by our revered http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=840 on Thu Sep 24, 2009 6:58 pm.
Pls recheck the source while waiting for Mathsguru' solution.
Submitted by VC's mum -
Herbie:
113 km/hHi I have a speed qn. Can help?
Town B is located between Town A and C.
At 2pm, a train left Town B and travelled towards Town C.
2.5 hr later, another train left Town B for Town A.
At 6pm, the two trains were 569km apart.
What was the speed of the train travelling towards Town C if it was going at 35km/h faster than the other train?
Tx -
huh! Can show the steps?
-
Herbie:
huh! Can show the steps?
Sure.
(ux1.5)+(u+35)4= 569
Solve for u and you will get u =78 km/h
(78+35) km/h = 113 km/h
Pls kindly wait for Dharma/Mathsguru's detailed solution.
Thanks.
Submitted by VC's mum. -
what does u represent? and how did you get the value of 1.5?
-
Vanilla Cake:
2pm to 4.30pmHerbie:
huh! Can show the steps?
Sure.
(ux1.5)+(u+35)4= 569
Solve for u and you will get u =78 km/h
(78+35) km/h = 113 km/h
Pls kindly wait for Dharma/Mathsguru's detailed solution.
Thanks.
Submitted by VC's mum.
Train towards C : Dist = 2.5Vc
Train towards A : Dist = 0
2pm to 6pm
Train towards C : Dist = 4Vc
Train towards A : Dist = 1.5Va
Total distance = 4Vc + 1.5Va = 569
Difference in speed =Vc – Va = 35
Solving gives Vc = 113km/h -
Herbie:
Using linear line approach to solving the qn. Pls see attachedHi I have a speed qn. Can help?
Town B is located between Town A and C.
At 2pm, a train left Town B and travelled towards Town C.
2.5 hr later, another train left Town B for Town A.
At 6pm, the two trains were 569km apart.
What was the speed of the train travelling towards Town C if it was going at 35km/h faster than the other train?
Tx
http://www.postimage.org/image.php?v=aVmj_5A -
sorry, what does Vc and Va stand for?
:shock: -
Newbies here, with ratio problem to solve, which goes this way as below:
The ratio of the number of daisies to the number of orchids in Basket A and Basket B are 2:1 and 2:7 respectively. Basket A has 2/3 times as many flowers as Basket B.
(a) Find the ratio of the number of daisies in Basket B to the number of daisies in Basket A.
(b) When 18 orchids are moved from Basket B to Basket A, the ratio of the number of daisies to the number of orchids in Basket A becomes 8:7. How many orchids are there in Basket A now?
Thanks. -
Herbie:
Sorry Herbie,sorry, what does Vc and Va stand for?
:shock:
Vc = speed of train towards Town C
Va = speed of train towards Town A
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login