37
The average of all odd numbers from 113 to 159 is ______.
- A135
- B134
- C133
- D136
Answer not set
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0
CCommunity
First we need to find the total number of odd numbers,
Last number = 159 and First number = 113
According to AP,
⇒ 159 = 113 + 2(n - 1)
⇒ n - 1 = 23
⇒ n = 24
∴ Sum of 24 odd numbers from 113 to 159 = 24/2 × [2 × 113 + 2(24 - 1)]
⇒ 12 × [226 + 46]
⇒ 3264
∴ Average = 3264/24 = 136
Last number = 159 and First number = 113
According to AP,
⇒ 159 = 113 + 2(n - 1)
⇒ n - 1 = 23
⇒ n = 24
∴ Sum of 24 odd numbers from 113 to 159 = 24/2 × [2 × 113 + 2(24 - 1)]
⇒ 12 × [226 + 46]
⇒ 3264
∴ Average = 3264/24 = 136
0
CCommunity
If there are arithmetic series
We can directly (113+159)/2 = 136
We can directly (113+159)/2 = 136