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# Statistics- probability Watch

A new housing development contains 100 properties of which 40 are semi-detached houses, 25 are detached houses, 20 are semi-detached bungalows and 15 are detached bungalows. a property is selected at random. Determine the probability that the property selected is:

a. either detached or a bungalow or both
i could do it if it were detached or a bungalow but 'or both' is confusing me.

thanks
2. (Original post by Flint_09)

A new housing development contains 100 properties of which 40 are semi-detached houses, 25 are detached houses, 20 are semi-detached bungalows and 15 are detached bungalows. a property is selected at random. Determine the probability that the property selected is:

a. either detached or a bungalow or both
i could do it if it were detached or a bungalow but 'or both' is confusing me.

thanks

contains 100 properties of which 40 are semi-detached houses, 25 are detached houses, 20 are semi-detached bungalows and 15 are detached bungalows

e: misread the question - don't do this! See below for proper solution.
3. It means either a detached house, a bungalow, or a detached bungalow. It isn't a well written question.

Be careful not to count detached bungalows twice.
4. (Original post by M_E_X)

contains 100 properties of which 40 are semi-detached houses, 25 are detached houses, 20 are semi-detached bungalows and 15 are detached bungalows

Ok, so we have:

40 semi-detached houses
25 detached houses
20 semi-detached bungalows
15 detached bungalows

The two in bold are relevant to our question. Obviously a house cannot be both a detached and semi-detached, so the number of houses which are both is zero, and we can ignore it.

Can you finish the problem from here? Hope I've helped!
i couldn't, sorry. it is not giving me the answer in the book, 0.60.
5. (Original post by Flint_09)
i couldn't, sorry. it is not giving me the answer in the book, 0.60.
EEP I misread the question - oops!

"either detached or a bungalow or both"

40 semi-detached houses
25 detached houses
20 semi-detached bungalows
15 detached bungalows

That's better. It's either a detached house, detached bungalow, or semi-detached bungalow.

Get it now? The question tricked me
6. (Original post by M_E_X)
EEP I misread the question - oops!

"either detached or a bungalow or both"

40 semi-detached houses
25 detached houses
20 semi-detached bungalows
15 detached bungalows

That's better. It's either a detached house, detached bungalow, or semi-detached bungalow.

Get it now? The question tricked me
thanks alot mate. you made it crystal clear now.

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