Let's denote the first term as a and the common difference as d.
We can write the first term as a and the last term as a + 5d (since there are 6 terms in total).
Given that the first term is 3/4 times the last term, we have the equation:
a = (3/4)(a + 5d)
Expanding the equation, we get:
4a = 3a + 15d
Simplifying, we have:
a = 15d
Since the sum of all terms is 210, we can express this as:
(6/2)(a + (a + 5d)) = 210
Simplifying further, we have:
3(a + (a + 5d)) = 210
3(2a + 5d) = 210
6a + 15d = 210
Since we know a = 15d from the previous equation, we can substitute this into the equation:
6(15d) + 15d = 210
90d + 15d = 210
105d = 210
Dividing both sides by 105, we get:
d = 2
Therefore, the common difference is 2.
The first and the last term of an arithmetic progression are in the ratio of 3:4. The sum of all terms is 210 and there are 6 terms in total. Commute common difference.
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