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

Let a1,a2,a3,,a15 be in an A.P
a1+a2++a10=A
a6+a7++a15=B If BA=200 and B+A=860, then find a15

Open in App
Solution


Let first term =a and common difference = d

A=(102)[2a+(101)d]=5(2a+9d)nowB=(102)[2a6+(101)d]=5[2{a+5d}+9d]=5[2a+19d]nowBA=200or5×10d=200d=(20050)=4andA+B=8605(2a+9d)+5(2a+19d)=860or20a+140d=860a=15thena15=a+14d=15+56=71


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