Lord Lycan
Registered User regular

Hi Folks,

I have an interview coming up next week and it involves a numerical reasoning test, the problem being I have a really hard time breaking these things down and understanding them.

Heres a couple examples:

**A car left Canterbury at 7.12 am and arrived in Birmingham, 180 miles distant at 10.57 am. What was its average speed in miles per hour?**

**An aircraft flies 930 miles in 75 minutes. How many miles does it fly in 4 hours 45 minutes assuming a constant speed?**

If anyone could recommend a good resource or method for tackling these I would be most appreciative.

I've done a book search and most have bad to no reviews, its really the methodology of how I should approach these types of questions that I'm after I guess.

I'm brushing up on my rusty math skills, but if anyone has any tips for any numerical reasoning approaches, please go ahead!

Cheers.

I have an interview coming up next week and it involves a numerical reasoning test, the problem being I have a really hard time breaking these things down and understanding them.

Heres a couple examples:

If anyone could recommend a good resource or method for tackling these I would be most appreciative.

I've done a book search and most have bad to no reviews, its really the methodology of how I should approach these types of questions that I'm after I guess.

I'm brushing up on my rusty math skills, but if anyone has any tips for any numerical reasoning approaches, please go ahead!

Cheers.

0

## Posts

If you read them right-to-left from the bottom it says "STD". I dunno if it helps you, but that's how I remembered this. Anyway, what you do is to hold your finger over the third you're trying to figure out. In your first example, you know the distance (D=180 miles) and the time (T=3 hours, 45 minutes= 225 minutes), and since the distance is at the top of the triangle you have D over T, or 180/225=0,8 miles per minute. Since there are 60 minutes in an hour, you multiply by 60 and get 48.

If they give you a "step up" it'll probably be two things moving at the same time, e.g. a train leaving Houston headed for Dallas and another train going the other way. What you want to do in that case is pretend that one train is standing still, by adding together the speeds.

I'm going to put the answer to the second example behind a spoiler so you can see if my method works for you.

Arangonmpm = 930/75 (because we travel 930 miles in 75 minutes)

That would mean our equation for solving this would be 285mpm = y.

If we solve for y, we get 285(12.4) = y, y = 3534.

If you're really good with algebra, try to make these word problems work like algebra.

bowenonEeveelutiononD=r*t, whereDis distance,ris rate, andtis time.Like for the second problem, what you first need to do is figure out the rate that the aircraft is traveling, so you solve for

rin the equation, like so:r = D / t= 930 miles / 1.25 hr = 744 miles/hr. Then using that rate you use another equation to solve for the distance with the new time traveled:D_2 = r * t_2= 744 (miles/hr) * 4.75 hr = 3534 miles, which is your final answer.I recommend keeping the units in the equations while you solve them, as they provide you with a quick sanity check to make sure that you didn't get too far off in your computation to end up with the wrong units for your answer.

SavantonUsing the first question as an example, you can tell that 7:12 + 3 Hours, +40 minutes + 5 minutes = 10:57 AM = 3.75 * 60 Minutes, travelling 3 * 60 Miles. The commonality is that both can be expressed as multiples of 60. The true answer is 48 mph (180 miles / 3.75 Hours = 48 miles / hour)

However, you can divide out the 60's and note that you go 3 miles for every 3.75 minutes, and 3.75 is close to 4. So every 4 minutes you go 3 miles, and you have 15 intervals of 4 minutes in one hour, so you go 3 * 15 = 45, or slightly more than 45 mph since 3.75 is smaller than 4. That's a close ballpark estimate, and is math you can easily do in your head.

TejsonOK, what is the actual

question?How many miles does it fly.How can I get the number of miles (that is, the distance)?

Distance (miles) = Time (minutes) * Speed (miles/minute)OK, how many minutes did it fly?

4 hr 45 min, or 285 minutesWell, what's the speed?

Don't know, but I know I want miles per minuteOK, can I calculate it?

Yes, the first sentence gives miles and minute right to us!What's the speed?

930 miles / 75 minutes = 12.4 miles/minuteOK, then how many miles did it fly?

285 minutes * 12.4 miles/minute = 3534 milesVrtra TheoryonThink about it for a second. What

isspeed? What's it measured in, exactly? Miles per hour. Hmm... What is a mile? A measure ofdistance. What is an hour? A measure oftime.Well then, if a mile is distance and an hour is time and speed is measured in miles per hour, then

speed = distance / time

or

a mile / hour (though really, distance can be measured in meters, inches, feet, etc.. and time can be measured in seconds, days, weeks, years, eons..)

Hopefully you see my point; if not well... I tried my best.

Demerdaron