wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A rifle man firing at a distant target and has only 10% chance of hitting it. The minimum number of rounds he must fire in order to have 50% chance of hitting it atleast once is

A
6
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
7
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
8
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
9
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B 7
The probability of hitting in one shot =10100=110
If he fires n shots, the probability of hitting atleast one
=1(1110)n=1(910)n=50%=50100=12(910)n=(12)
n{log9log10}=log1log2n{2log31}=0log2n=log212log3=0.301030012×0.4771213=6.6
Hence, n =7

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Events
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon