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The second and seventh term of a geom. progression are 18 and 4374 respectively find the (a) common ratio (b) sum of 4th and 8th terms (c) sum of the first 10 terms.
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= . = 18 (1)
= . = 4374 (2)
Divide (2) by (1). You will get
= = 243.
Hence, = = 3.
It implies = = = 6.
Now, when you know = 6 and = 3, you can calculate all remaining values.