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Find the average of first 30 multiples of 7.
- A94.8
- B99.6
- C 104.4
- D108.5
Answer not set
Discussion 1
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CCommunity
First multiple of 7 is = 7
Second multiple of 7 is = 7 × 2 = 14
Similarly 30th multiple of 7 is = 7 × 30 = 210
So, AP is 7 + 14 + ……. + 210
∴ Average of AP = (First term + Last term)/2 = (7 + 210)/2 = 217/2 = 108.5
Second multiple of 7 is = 7 × 2 = 14
Similarly 30th multiple of 7 is = 7 × 30 = 210
So, AP is 7 + 14 + ……. + 210
∴ Average of AP = (First term + Last term)/2 = (7 + 210)/2 = 217/2 = 108.5