Sequence And Series Question 438
Question: The four arithmetic means between 3 and 23 are
[MP PET 1985]
Options:
A) 5, 9, 11, 13
B) 7, 11, 15, 19
C) 5, 11, 15, 22
D) 7, 15, 19, 21
Show Answer
Answer:
Correct Answer: B
Solution:
Let four arithmetic means are $ A_1,A_2,\ A_3 $ and $ A_4 $ . So $ 3,\ A_1,\ A_2,\ A_3,\ A_4,\ 23 $
$ \Rightarrow $ $ T_6=23=a+5d $
$ \Rightarrow $ $ d=4 $ Thus $ A_1=3+4=7,\ A_2=7+4=11,\ $ $ A_3=11+4=15,,A_4=15+4=19 $
BETA
