The first term of an AP is 5, the last term is 45 and the sum of all its terms is 400. find the number of terms and common difference of the AP. (I NEED FULL SOLUTION STEP BY STEP
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a= 5
L= 45
Sn= 400
n(a+L)/2= 400
n(5+45)=800
n*50 = 800
n = 16
Now,
45 = a+(n-1)d
45 = 5 + (16-1)d
40 = 15d
8 = 3d
d = 8/3
Hope this is correct and will help you
Please mark as brainliest if you liked the solution
L= 45
Sn= 400
n(a+L)/2= 400
n(5+45)=800
n*50 = 800
n = 16
Now,
45 = a+(n-1)d
45 = 5 + (16-1)d
40 = 15d
8 = 3d
d = 8/3
Hope this is correct and will help you
Please mark as brainliest if you liked the solution
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