the first and the last terms of an A.P. are 5 and 45 respectively. If the sum of all it's term is 400, find the common difference and the number of terms.
Answers
Answered by
49
Answer:First term, a=5
Last term, l=45
Common difference = d
Sum of AP of n terms = (n/2)(a+l)
Sum = 400
On substituting values of a & l,
We get, n=16
l=a+(n-1)d
On substituting values of a,l & n
We get, d= 8/3
\
Answered by
2
Answer:
above one is the right answer ☺️
Similar questions