Venn Diagram Car Park Problem: L-plates & GB-plates Explained

[Natasha1]

Homework Statement

In a car park there are 25 cars, 5 have L-plates, 12 have GB-plates and 12 have neither.
1) How many have an L-plate but not a GB-plate?
2) How many have a GB-plate and an L-plate?

Homework Equations

None here really

The Attempt at a Solution

I got four different drawings each with two venn diagrams.

L-plate =2
Both L and GB-plate = 3
GB-plate = 9

L-plate =1
Both L and GB-plate = 4
GB-plate = 8

L-plate =3
Both L and GB-plate = 2
GB-plate = 10

L-plate =4
Both L and GB-plate = 1
GB-plate = 11

Where am I going wrong?

1) How many have an L-plate but not a GB-plate?
it could be 2, 1, 3 or 4 ?? Not sure which one and why?

2) How many have a GB-plate and an L-plate?
it could be 3, 4, 2 or 1 ?? Not sure which one and why?

 

[SammyS]

Homework Statement

In a car park there are 25 cars, 5 have L-plates, 12 have GB-plates and 12 have neither.
1) How many have an L-plate but not a GB-plate?
2) How many have a GB-plate and an L-plate?

Homework Equations

None here really

The Attempt at a Solution

I got four different drawings each with two venn diagrams.

L-plate =2
Both L and GB-plate = 3
GB-plate = 9

That leaves how many cars without tags?

L-plate =1
Both L and GB-plate = 4
GB-plate = 8

That leaves how many cars without tags?

L-plate =3
Both L and GB-plate = 2
GB-plate = 10

That leaves how many cars without tags?

L-plate =4
Both L and GB-plate = 1
GB-plate = 11

That leaves how many cars without tags?

Where am I going wrong?

1) How many have an L-plate but not a GB-plate?
it could be 2, 1, 3 or 4 ?? Not sure which one and why?

2) How many have a GB-plate and an L-plate?
it could be 3, 4, 2 or 1 ?? Not sure which one and why?

Some of your drawings of Venn diagrams must be incorrect

 

[Rumplestiltskin]

Homework Statement

In a car park there are 25 cars, 5 have L-plates, 12 have GB-plates and 12 have neither.
1) How many have an L-plate but not a GB-plate?
2) How many have a GB-plate and an L-plate?

Start with the 'neithers' -- they're the easiest, no confusion. Place them outside your Venn diagram.
That leaves 13 cars; your three remaining figures should add to 13.

 

[Natasha1]

I think I've got it... It must be

L-plate =1
Both L and GB-plate = 4
GB-plate = 8
Neither plates (outside both Venn diagrams) = 12
As the total is 13 (total of L-plates, GB-plates or both must = 13)

1) How many have an L-plate but not a GB-plate?
Is 1
2) How many have a GB-plate and an L-plate?
Is 4

Could someone please check and let me know if it's right? Many thanks :)

 

[Rumplestiltskin]

Could someone please check and let me know if it's right? Many thanks :)

Bingo :)

 

[Natasha1]

Many thanks :)