##### Vivian Ang
Asked 5 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

How to do this question?

Replies 1

##### Zhong Shu Hao

Distance travelled = 15m/s x 102s = 1530m Length of tunnel = 1530m - 135m = 1395m

2 years ago

##### Vivian Ang
Asked 5 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

How to do this question?

Replies 1

2 years ago

##### Vivian Ang
Asked 5 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

How to do this question?

Replies 1

After t hours both trains meet. Distance travelled by A = 180t By B = 170t Total = 1050 = 180t + 170t = 350t t = 1050/350 =3 hrs Distance travelled by A = 180 x 3 = 540 and by B = 510km

2 years ago

##### Chua Choon Hock
Asked 5 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

Replies 11

2 years ago
##### Chua Choon Hock

Thanks. Vera are u a full-time teacher ?

2 years ago
##### Chua Choon Hock

Vera in this case 8 is the Unit ?

2 years ago
##### Chrissy Ong

Hi what level is this ?

2 years ago

P6

2 years ago
##### Vera Koh

8 refers to the number of times we have to swop 6 pencils n 6 pens.. i wun say it's a unit.

2 years ago

Thanks Vera

2 years ago
##### Vera Koh

haha.. i'm not a full-time teacher.

2 years ago
##### Soo Vei Li

Choon Hock, here're two similar qns which were posted in early May. You can look through the photos posted on those dates and give them to your child for further practice...

2 years ago

2 years ago

Thanks

2 years ago

##### Liu Gaoyuan
Asked 5 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

I am quite confused by the answer given. The question: a train takes 24 seconds to pass a tunnel which is 560 m long. It takes 16 seconds to cross a bridge which is 416m long.(a) What is the speed of the train?(b) How long is the train?The given answer is (a) 18m/s(b) 128m

Replies 5

##### Liu Gaoyuan

(a) The speed is calculated as (560-416)/(24-16)=18m/s This is not an issue. (b) the given answer is 560 - 24*18=128m, or 416-16*18=128m

2 years ago
##### Liu Gaoyuan

Shouldn't the total distance to cross a bridge be (the length of the bridge + the length of the train)? Or a train is considered to "cross" the bridge already so long as the head of the train has cross he bridge?

2 years ago
##### Vera Koh

hmm.. if just the "head" cross the bridge, then speed shd b 560/24 or 416/16.. but both of these yield different answers.. i am equally confused w the solution..

2 years ago

A

2 years ago

A

2 years ago