please answer my questions
Answers
1. First ten prime numbers are 2,3,5,7,11,13,17,19,23,29.
Mode of a observation is that number which has highest frequency in other words which is repeated many times. In the above observation no number is repeated.
So mode is zero.
2. Let the combined marks of all 20 students be x.
Given mean(average) of their marks is 150.
∴ x/20 = 150
x=3000.
So sum of marks of all students is 3000.
3. log₂ 4, log₃ 27, log₂ 16, log₂ 2.
Remember logₐ a =1 and logₐ bⁿ = n logₐ b.
Now the series is log₂ 2², log₃ 3³, log₂ 2⁴, log₂2
= 2log₂2, 3log₃3, 4log₂2, log₂2
=2, 3, 4, 1.
Arrange them in ascending or descending order,
= 1, 2, 3, 4.
Median is middle term.
Since there are two middle terms their average would be median.
i.e median = 2+3/2 = 5/2 = 2.5.
4. Given arithmetic mean(average) of x, x+3, x+6, x+9, x+12 is 10.
i.e x+x+3+x+6+x+9+x+12/5 = 10
5x + 30 = 50
5x = 20
x = 4.
Therefore the observation is 4,7,10,13,16.
Since median is middle term the median of above observation is 10.