BOND Third papers

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anowicka
Posts: 48
Joined: Wed Jul 07, 2010 12:03 pm

BOND Third papers

Post by anowicka »

Please help.

Find the length of a queue of 21 cars (each car is 4 m long).
There is a space of 1 m between each pair of cars.

Answer given is 104 m

I only got 94 m:
21 cars x 4m = 84m
10 spaces x 1m = 10m

10m+84m =94m

Why is 104m , I have no idea., please could you have a look into this.
chicko-mum
Posts: 294
Joined: Wed Apr 28, 2010 12:19 pm

Re: BOND Third papers

Post by chicko-mum »

I think the question means there is a 1m space between each car and the next one -
car : 1m : car : 1m : car etc...
that would create 20 x 1m spaces not 10.
It can't be a 1m space after 2 cars as that would require an even number of cars and there are 21 in all.

So 21 cars = 84m plus 20m spaces = 104m

hth
Tea Lover
Posts: 38
Joined: Tue Mar 04, 2008 12:55 pm

Re: BOND Third papers

Post by Tea Lover »

There are 21 cars, each 4m long, so 21x4m = 84 m gives the total length of the cars.

Then you have to work out the total length of the gaps between the cars, which is
20x 1m, giving 20m.

(The number of gaps between the cars = number of cars -1, so 21-1=20, i.e., 20 gaps. If in doubt, always try these things with small numbers first. For example, if there were 2 cars, there would be 1 gap. If there were 3 cars, there would be 2 gaps, so there is always one less gap than the number of cars.)

The total length of the cars plus the total length of the gaps gives the length of the queue of 21 cars, so
84m + 20m = 104m.

I hope this helps.


I see Chicko-mum has already answered, but it took me a while to write the post so I'll going to post it anyway. :D
anowicka
Posts: 48
Joined: Wed Jul 07, 2010 12:03 pm

Re: BOND Third papers

Post by anowicka »

Thank you for your replies, Yes, they must mean space between each car rather then between each pair of cars.
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