# Find the 60 th term of the AP 8,10,12,......,If it has a total of 60 terms and hence find the sum of its last 10 terms.

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by 426ri543

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by 426ri543

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The Brainliest Answer!

a=8,d=10-8=2

as we know,an=a+(n-1) x d

a₆₀ =8+(60-1)2

=8+118=126

so,now we find the sum of n terms

s₆₀=60/2[2 x 8 +(60-1)2]

=30[16+118]

=4020

as we taken last ten terms =60-10=50

so,

s₅₀=50/2[2×8+(50-1)2]

=25[16+98]

=2850

now sum of last ten terms= s₆₀-s₅₀=4020=-2850 =1170

d=10-8=2

tn=a+(n-1)d

T60= 8+(60-1)2

=8+59*2

=8+118

=126

now,

sn=n/2(2a+(n-1)d)

S60=60/2(2*8+(60-1)2)

=30(16+118)

=4020

S50=50/2(2*8+(50-1)2)

=25(16+49*2)

= 25(16+98)

=2850

now sum of last terms=S60-S50=4020-2850= 1170