Question

ϙᴜᴇsᴛɪᴏɴ :-

● ɪɴ ᴀ ɢʀᴏᴜᴘ ᴏғ 120 ᴘᴇᴏᴘʟᴇ, 90 ʜᴀᴠᴇ ᴀɴ ᴀɢᴇ ᴏғ ᴍᴏʀᴇ 30 ʏᴇᴀʀs, ᴀɴᴅ ᴛʜᴇ ᴏᴛʜᴇʀs ʜᴀᴠᴇ ᴀɴ ᴀɢᴇ ᴏғ ʟᴇss ᴛʜᴀɴ 20 ʏᴇᴀʀs. ɪғ ᴀ ᴘᴇʀsᴏɴ ɪs sᴇʟᴇᴄᴛᴇᴅ ᴀᴛ ʀᴀɴᴅᴏᴍ ғʀᴏᴍ ᴛʜɪs ɢʀᴏᴜᴘ, ᴡʜᴀᴛ ɪs ᴛʜᴇ ᴘʀᴏʙᴀʙɪʟɪᴛʏ ᴛʜᴇ ᴘᴇʀsᴏɴ's ᴀɢᴇ ɪs ʟᴇss ᴛʜᴀɴ 20?



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ʜɪ ɢᴜʏs sᴏ ɪғ ᴀɴʏᴏɴᴇ ɴᴇᴇᴅ ᴛʜᴀɴᴋs sᴏ ɢɪᴠᴇ ᴍᴇ 20 ᴛʜᴀɴᴋs ɪ ᴡɪʟʟ sᴜʀᴇʟʏ ɢɪᴠᴇ ʏᴏᴜ 40 ᴛʜᴀɴᴋs
ʙᴜᴛ ʜᴇʀᴇ ᴅᴏɴ'ᴛ sᴘᴀᴍ ᴊᴜsᴛ ғᴏʀ ᴛʜᴀɴᴋs
ɪғ ᴜ ᴡɪʟʟ ɢɪᴠᴇ ᴍᴇ 20 ᴛʜᴀɴᴋs ɪ ᴡɪʟʟ ɢɪᴠᴇ ɪғ ɪ ᴅɪᴅɴ'ᴛ ɢɪᴠᴇ ᴜ ᴛʜᴀɴᴋs ʀᴇᴛᴜʀɴ sᴏ ᴀɴsᴡᴇʀ ɪɴ ᴍʏ ᴀɴᴏᴛʜᴇʀ ϙᴜᴇsᴛɪᴏɴ

ᴛʜᴀɴᴋ ʏᴏᴜ !


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Answer 1

Answer:

Total number of people = 120

No. of people having age more than 30 yrs. = 90

No. of people having age less than 20 yrs. = 120 - 90 = 30

$probability = \frac{no \: of \: favourable \: outvcome}{no \: of \: total \: outcomes}$

30/120

1/4

Therefore, probability of a person having age less than 20 yrs. is 1/4.

Answer 2

Answer:

$\tt \: Total \: number \: of \: people = 120$

$\tt \: No. of \: people \: having \: age more \: than \: 30 yrs. = 90$

$\sf \: No. of \: people \: having \: age \: less \: than \: 20 yrs. = 120 - 90 = 30$

$\sf \: probability = \frac{no \: of \: favourable \: outvcome}{no \: of \: total \: outcomes}$

$\small\underline\mathrm\purple {30/120}$

$\small\underline\mathrm\purple {1/4}$

$\tt \: Therefore, probability \: of \: a \: \: person \: having \: age \: less \: than \: 20 yrs. is 1/4.$

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