the 8th term of an Ap is half of its 2nd term and 11th term exceed one third of its 4th term by 1. Find the 15th term
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nth term of ap is a+(n-1)*d where a is the first term and d is the difference between terms.
so a+(8-1)d=0.5(a+(2-1)d)
a+7d=0.5a+0.5d, so 0.5a=-6.5d, a=-13d
a+(11-1)d=(1/3(a+(4-1)d))+1
a+10d=1/3(a+3d)+1
3a+30d=a+3d+3
2a-3=-27d
since a=-13d
-26d-3=-27d
d=3
a=-39
so 15th term is
-39+14*3
=3
so a+(8-1)d=0.5(a+(2-1)d)
a+7d=0.5a+0.5d, so 0.5a=-6.5d, a=-13d
a+(11-1)d=(1/3(a+(4-1)d))+1
a+10d=1/3(a+3d)+1
3a+30d=a+3d+3
2a-3=-27d
since a=-13d
-26d-3=-27d
d=3
a=-39
so 15th term is
-39+14*3
=3
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