Speed Distance Time for Dummies

Original post by Durden561

Revising for the cbat, mainly sdt questions just now. using the speed distance time website, dont have a problem with any of the standard questions but it often pops up questions with really big numbers. Anybody here who has done the cbat, can you confirm if they actually use such large and awkward numbers ? Also does anyone have any useful methods for solving such questions, a little bit faster ?

At 135 mph, how long does it take to travel 18 miles?
At 192 mph, how long does it take to travel 112 miles?
At 52 mph, how long does it take to travel 91 miles?
What speed covers 21 miles in 10 hours and 30 mins?

Thanks

Look for cheeky shortcuts - for example, 9 goes into both 135 and 18. So you can cancel this down to 2/15 (Time = Distance / speed) and therefore 8/60 = 8 mins.

Keep practising.

Look for things that are divisible by 3, 6, 12, 15 etc - most questions on the CBAT will generally make it easy for you.

Original post by Durden561

Revising for the cbat, mainly sdt questions just now. using the speed distance time website, dont have a problem with any of the standard questions but it often pops up questions with really big numbers. Anybody here who has done the cbat, can you confirm if they actually use such large and awkward numbers ? Also does anyone have any useful methods for solving such questions, a little bit faster ?

At 135 mph, how long does it take to travel 18 miles?
At 192 mph, how long does it take to travel 112 miles?
At 52 mph, how long does it take to travel 91 miles?
What speed covers 21 miles in 10 hours and 30 mins?

Thanks

Look for patterns based around 6, 10 and 12 (and 3 and 15 and thereafter any multiples) because if you can find one of the numbers you have to work with, say 135, can be divided by one of those numbers, then try the other figure and see if it can be divided by the same. Or just reduce the numbers to simpler terms until you can see a pattern.

So look at 135 - 45 goes into it 3 times, so you know that you go 45 miles in 20 minutes, 22.5 miles in 10 minutes. Now hopefully you can see that 4.5 goes into 18 4 times and 22.5 5 times, so if 5 times = 10 minutes, 4 times must = 8 minutes.

192 mph, how long to travel 112 miles? first off, you can ball park the answer is a little more than half an hour (112 is a little more than half 192) so maybe you can see how much more than half (half 192 = 96, difference between 96 and 112 is 16) - then I can see there are 12 16s in 192, because there are 10 in 160, remainder 32, which has 2 and now i've found my key to time. There are 12 sets of 16 in the speed, and 12 sets of 5 minutes in an hour, so 112 must take 5 minutes more than half an hour, or 35 minutes.

52 mph, how long to do 91 miles - immediately I know the answer is going to be just less than 2 hours, but how much less? In 2 hours i'd travel 104 miles, the difference between 91 and 104 is 13, that's crappy number - oh not it's not - think playing cards, it's a quarter of 52, so 91 miles takes a quarter of an hour less than 2 hours, or 1 hour 45 minutes.

This all sounds painfully long winded, but if you practice, you quickly start to recognise the patterns, and you keep the logic of what you are trying to achieve in your head and you avoid making gross errors.

The 4th one is too obvious to write out!

Thanks!

how long will it take if i do 65mph and the distance is 110 thankyou

Reply 586

NobleWizard

7

So I just want to add a little more info for those that are still interested, in the cbat for the airbourne numerical test you work in m/min ranging from 3 to 7 and the distance for each leg is always below 100. I'm sure that will help at least someone and help lower the stress for taking the test. So just know your times tables as best you can for it.

Reply 587

Quebanks

1

How long will it take to finish 600mi going the speeds of 68mph

Reply 588

Original post by Quebanks

How long will it take to finish 600mi going the speeds of 68mph

The questions aren’t that hard, they are normally divisible by 3/6/10/15/30/40/45 etc

Reply 589

Maximilian118

I'm just trying to find my way of doing things with SDT.
Mix and matching various different ways of making my calculations.

I have two questions...
Can anybody tell me in a definitive way the easiest way to make calculations for each discipline? I.E Speed, Distance and Time.
I JUST want some sort of template on which to build from because I'm receiving so many mixed messages.

It seems that sometimes using the easiest methods won't work if the question doesn't have numbers that match well or is beyond a certain threshold.
For example...

90 Miles at 72 MPH?
A really nice way I've found is this:

What is the speed in relation to 60m?
72 = 6/5
Then take the Denominator (5) and X Distance by that number.
90 X 5 = 450
Then take that number and / by the Numerator to find the answer.
450 / 6 = 75 or 1h 15m

However, this method is very difficult for a question like:

221 Miles at 170 MPH?
I can't figure out a way of breaking a question like that down even on paper without a calc!

My second question would be... What can I do about a cheeky 1-5 minutes here and there?
Small numbers like that just play havoc on my fractions making the denominator something like 15!
Making the method above rather difficult!

For example:

What speed covers 13 miles in 1 hour and 5 mins?
What speed covers 16 miles in 1 hour and 4 mins?

Finding speed here is very annoying due to those pesky 5 and 4 mins.

Any advice would be really appreciated!

Reply 590

Original post by Maximilian118

I'm just trying to find my way of doing things with SDT.
Mix and matching various different ways of making my calculations.

I have two questions...
Can anybody tell me in a definitive way the easiest way to make calculations for each discipline? I.E Speed, Distance and Time.
I JUST want some sort of template on which to build from because I'm receiving so many mixed messages.

It seems that sometimes using the easiest methods won't work if the question doesn't have numbers that match well or is beyond a certain threshold.
For example...

90 Miles at 72 MPH?
A really nice way I've found is this:

What is the speed in relation to 60m?
72 = 6/5
Then take the Denominator (5) and X Distance by that number.
90 X 5 = 450
Then take that number and / by the Numerator to find the answer.
450 / 6 = 75 or 1h 15m

However, this method is very difficult for a question like:

221 Miles at 170 MPH?
I can't figure out a way of breaking a question like that down even on paper without a calc!

My second question would be... What can I do about a cheeky 1-5 minutes here and there?
Small numbers like that just play havoc on my fractions making the denominator something like 15!
Making the method above rather difficult!

For example:

What speed covers 13 miles in 1 hour and 5 mins?
What speed covers 16 miles in 1 hour and 4 mins?

Finding speed here is very annoying due to those pesky 5 and 4 mins.

Any advice would be really appreciated!

Hi Max

For the first one;

You know it’s going to take at least an hour, so you have 18 miles left to travel at 72mph.

Time =distance/speed

so t= 18/72
t = 1/4
and then times the denominator by 15.

answer 1hr15

Same method for Q2: 221 miles at 170mph

you do 170miles in an hour.

so you need to know how much longer the additional 51 miles take you at 170mph.

t = d/t
t= 51/170
(17 goes into 51)
t= 3/10
t = 18

1hr18 mins

Reply 591

Maximilian118

Original post by EconWarrior

Hi Max

For the first one;

You know it’s going to take at least an hour, so you have 18 miles left to travel at 72mph.

Time =distance/speed

so t= 18/72
t = 1/4
and then times the denominator by 15.

answer 1hr15

Same method for Q2: 221 miles at 170mph

you do 170miles in an hour.

so you need to know how much longer the additional 51 miles take you at 170mph.

t = d/t
t= 51/170
(17 goes into 51)
t= 3/10
t = 18

1hr18 mins

Thanks for the reply!

Ok but what do I do about a question like 110miles over 4h 30m/270mins?

7's seem to be really difficult.
I can simplify the fraction by /10 to make 11/27 but 7's don't fit into 60.
I can't simplify more because 11 is a prime number and to simplify 110/270 by /10+ is just too hard to do in my head.

Reply 592

Original post by Maximilian118

Thanks for the reply!

Ok but what do I do about a question like 110miles over 4h 30m/270mins?

7's seem to be really difficult.
I can simplify the fraction by /10 to make 11/27 but 7's don't fit into 60.
I can't simplify more because 11 is a prime number and to simplify 110/270 by /10+ is just too hard to do in my head.

The questions you get at OASC won’t be this tricky

Reply 593

Maximilian118

Original post by EconWarrior

The questions you get at OASC won’t be this tricky

I've come across a number like 701 with SDT (with fuel) on the CBAT app.
What can I do with this distance number?!

Reply 594

donald37

i checked with reeds website for a online teaching and training level 5 and it give me this website 5starscourses but i am not sure if is trusted website or accredited any help it will appreciated thanks.

Reply 595

WedgeAnt

7

Could you be clear about what it is you want to learn and why? I haven't clicked your link because it's not clear why you're asking what you asked.

If all you need is practice for the sdt for the AST or CBAT then there are multiple free tools to practice quick sums

Reply 596

donald37