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Maths Puzzle
tickets number form 1 to 20 are mixed up and then a ticket is drawn at random what is the probability that ticket drawn has number which is a multiple of 3 or 5?
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- the ways to draw 1 ticket from 20 =20c1=20
total multiple of 3 or 5=(3,5,6,9,10,12,15,18,20)
but 15 is multiple of both 3 and 5
so it is not considered bcoz
n(aub)=n(a)+n(b)-n(a intersection b)
so probability=8/20=2/5
- 11 years agoHelpfull: Yes(2) No(0)
- no. of spaces=(1,2,3,4,5,...,19,20).
event of getting a multiple of 3 or 5
= (3,6,9,12,15,18,5,10,20)
= 9/20. answer - 11 years agoHelpfull: Yes(0) No(2)
- (6/20)+(4/20)-(1/20)=9/20
- 11 years agoHelpfull: Yes(0) No(0)
- numbers divisible by 3(3,6,9,12,15,18)=6/20
numbers divisible by 5(5,10,15,20)=4/20
15 is divisible by both 3 and 5 so 1/20
6/20+4/20-1/20=9/20 - 11 years agoHelpfull: Yes(0) No(0)
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