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Average of five numbers is 61. If the average of first and third numbers is 69 and the average of second and fourth numbers is 69, what is the fifth number ?
- A31
- B29
- C25
- D35
Answer not set
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0
CCommunity
Solution
Let the numbers be $A_1 , A_2 , A_3 , A_4 , A_5$
=> $A_1 + A_2 + A_3 + A_4 + A_5 = 61 * 5 = 305$
Also, $A_1 + A_3 = 69 * 2 = 138$
and $A_2 + A_4 = 69 * 2 = 138$
=> $A_5 = 305 - 138 - 138 = 29$
Let the numbers be $A_1 , A_2 , A_3 , A_4 , A_5$
=> $A_1 + A_2 + A_3 + A_4 + A_5 = 61 * 5 = 305$
Also, $A_1 + A_3 = 69 * 2 = 138$
and $A_2 + A_4 = 69 * 2 = 138$
=> $A_5 = 305 - 138 - 138 = 29$
0
CCommunity
Solution
Let the numbers be $A_1 , A_2 , A_3 , A_4 , A_5$
=> $A_1 + A_2 + A_3 + A_4 + A_5 = 61 * 5 = 305$
Also, $A_1 + A_3 = 69 * 2 = 138$
and $A_2 + A_4 = 69 * 2 = 138$
=> $A_5 = 305 - 138 - 138 = 29$
Let the numbers be $A_1 , A_2 , A_3 , A_4 , A_5$
=> $A_1 + A_2 + A_3 + A_4 + A_5 = 61 * 5 = 305$
Also, $A_1 + A_3 = 69 * 2 = 138$
and $A_2 + A_4 = 69 * 2 = 138$
=> $A_5 = 305 - 138 - 138 = 29$