Question

times the numerator. Determine the fraction.
The first term of an A.P. is 5, the last term is 45 and the sum is 400. Find the number of
terms and the common difference,
​

Answer 1

Step-by-step explanation:

given;

a=5

an=last term=45

sn400

now;

sn= n\2[a+l]

400=n\2(5+45)

400=n\2×50

n=400/25

n=16

an =a+(n-1)d

45=5+(16-1)d

45-5=15d

40/15=d

d=8/3