Q28 of 145 Page 410

The mean of 2, 7, 6 and x is 15 and the mean of 18, 1, 6, x and y is 10. What is the value of y?

Given: mean of 2, 7, 6 and x is 15


Mean =


⇒ 15 =


⇒ 60 = 15 + x


⇒ x = 60 – 15 = 45 …(i)


Also, given that mean of 18, 1, 6, x and y is 10


10 = [∵ mean = 10]


⇒ 50 = 25 + 45 + y = 70 + y [from equation (i)]


⇒ y = 50 – 70 = - 20


Thus, y = - 20

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The mean of 20 numbers is zero. Of them, at the most, how many may be greater than zero?

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Match the following columns:























Column I



Column II



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Each question consists of two statements, namely, Assertion (A) and Reason (R). For selecting the correct answer, use the following code:











Assertion (A)



Reason (R)



If the median and mode of a frequency distribution are 150 and 154 respectively, then its mean is 148.



Mean, median and mode of a frequency distribution are related as: mode = 3 median - 2 mean.