Question

Which term of the A. P. 3, 7, 11, 15,....... is 75? ​

Answer 1

Answer:

Here, a=3

d=7-3=4

an=75

We know that an=a+(n-1)d

so, 75=3+(n-1)4

75=3-4+4n

76=4n

n=76/5=19

Answer 2

Answer:

a=3

d=7-3=4

an=75

an = a+(n-1)d

75 = 3+(n-1)4

75 - 3 =4n-4

72 = 4n - 4

72+4=4n

76=4n

76/4 = n

n = 19