Hi
Please can someone help me with this problem.
I know the formula.
a + (n-1) d
In this case a is 23 and d is -3
But what is n?
How do you approach this?
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Arithmetic progression
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I know the formula, but I don't know what this formula is for 
Is it to find n-th member of arithmetic progression?
a is the first member
d is the difference between a_i, a_(i-1)
for example
0, 2, 4, 8, 10, ...
a = 0, d = 2
So 5-th member a_5 = a+5d = 10
Is it to find n-th member of arithmetic progression?
a is the first member
d is the difference between a_i, a_(i-1)
for example
0, 2, 4, 8, 10, ...
a = 0, d = 2
So 5-th member a_5 = a+5d = 10
