Math miscellaneousEasy
Question
Let the sum of the first three terms of an A.P. be 39 and the sum of its last four terms be 178. If the first term of this A.P. is 10, then the median of the A.P. is :
Options
A.29.5
B.26.5
C.28
D.31
Solution
10 + (10 + d) + (10 + 2d) = 39 ⇒ d = 3
tn = 10 + (n - 1)3 = 3n + 7
Also (3n + 7) + (3n - 3 + 7) + (3n - 9 + 7) = 178
⇒ n = 14
∴ median =
= 29.5
tn = 10 + (n - 1)3 = 3n + 7
Also (3n + 7) + (3n - 3 + 7) + (3n - 9 + 7) = 178
⇒ n = 14
∴ median =
= 29.5Create a free account to view solution
View Solution FreeMore Math miscellaneous Questions
Let a, b, c and d are real numbers (d > a > b > c). If mean and median of the distribution a, b, c, d are 5 and...If A = then...If f (x) = xn, then the value of f(1) is...The number of real solutions of the equation x2 - 3 |x| + 2 = 0 is...The number of five digit numbers that contains digit 7 exactly once is if digits may be repeated)...