The 25th term of an A.P is 173. Find the sum of the 7th and 15th term if the common difference is 7
Just use your formulas.
a+24d = 173
d = 7
Now find a, and then
(a+6d)+(a+14d)
Thanks
To find the 25th term of an arithmetic progression (A.P), we can use the formula:
an = a1 + (n-1)d
where:
an = the nth term
a1 = the first term
n = the position of the term
d = the common difference
In this case, we are given:
a25 = 173
d = 7
Substituting these values into the formula, we can find a1:
173 = a1 + (25 - 1) * 7
173 = a1 + 24 * 7
173 = a1 + 168
a1 = 173 - 168
a1 = 5
Now we can find the 7th term and the 15th term using the same formula:
a7 = a1 + (7 - 1) * 7
a7 = 5 + 6 * 7
a7 = 5 + 42
a7 = 47
a15 = a1 + (15 - 1) * 7
a15 = 5 + 14 * 7
a15 = 5 + 98
a15 = 103
Finally, to find the sum of the 7th and 15th terms, we add them together:
Sum = a7 + a15
Sum = 47 + 103
Sum = 150
Therefore, the sum of the 7th and 15th term of the arithmetic progression is 150.