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प्रश्न
The mean of a, b, c, d and e is 28. If the mean of a, c and e is 24, then mean of b and d is
विकल्प
24
36
26
34
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उत्तर
34
Explanation;
Hint:
Mean = 28
a + b + c + d + e = 28 × 5 = 140
= 140 ...(1)
But `("a" + "c" + "e")/3` = 24
a + c + e = 72
a + b + c + d + e = 140
b + d + 72 = 140
b + d = 140 – 72
= 68
Mean = `68/2`
= 34
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