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The average (arithmetic mean) of a, b, and c is 70, and the
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09 Mar 2019, 11:18
09 Mar 2019, 11:18
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The average (arithmetic mean) of a, b, and c is 70, and the average (arithmetic mean) of d and e is 120. What is the average (arithmetic mean) of a, b, c, d, and e?
A. 84
B. 90
C. 95
D. 96
E. 100
A. 84
B. 90
C. 95
D. 96
E. 100
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The average (arithmetic mean) of a, b, and c is 70, and the
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09 Mar 2019, 15:53
09 Mar 2019, 15:53
1
Carcass wrote:
The average (arithmetic mean) of a, b, and c is 70, and the average (arithmetic mean) of d and e is 120. What is the average (arithmetic mean) of a, b, c, d, and e?
A. 84
B. 90
C. 95
D. 96
E. 100
A. 84
B. 90
C. 95
D. 96
E. 100
The average (arithmetic mean) of a, b, and c is 70
So, (a + b + c)/3 = 70
This also means a + b + c = 210
The average (arithmetic mean) of d and e is 120
So, (d + e)/2 = 120
This also means d + e = 240
What is the average (arithmetic mean) of a, b, c, d, and e?
Average of all 5 numbers = (a + b + c + d + e)/5
= (210 + 240)/5
= 450/5
= 90
Answer: B
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The average (arithmetic mean) of a, b, and c is 70, and the
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08 Jul 2021, 08:16
08 Jul 2021, 08:16
1
Theory
The average (arithmetic mean) of a, b, and c is 70
Sum of a, b, c = Average * 3 = 70 * 3 = 210
=> a + b + c = 210 ...(1)
The average (arithmetic mean) of d and e is 120
Sum of d, e = Average * 2 = 120 * 2 = 240
=> d + e = 240 ...(2)
The average (arithmetic mean) of a, b, c, d, and e
Average = Sum of a, b, c, d, and e / 5 = \(\frac{a + b + c + d + e }{ 5}\) = \(\frac{210 + 240 }{ 5}\) (from (1) and (2))
= \(\frac{450}{5}\) = 90
So, Answer will be B.
Hope it helps!
Watch the following video to Learn the Basics of Statistics
- ➡ Average = Sum of all the Values / Total Number of Values
➡ Sum of All the values = Average * Total Number of Values
The average (arithmetic mean) of a, b, and c is 70
Sum of a, b, c = Average * 3 = 70 * 3 = 210
=> a + b + c = 210 ...(1)
The average (arithmetic mean) of d and e is 120
Sum of d, e = Average * 2 = 120 * 2 = 240
=> d + e = 240 ...(2)
The average (arithmetic mean) of a, b, c, d, and e
Average = Sum of a, b, c, d, and e / 5 = \(\frac{a + b + c + d + e }{ 5}\) = \(\frac{210 + 240 }{ 5}\) (from (1) and (2))
= \(\frac{450}{5}\) = 90
So, Answer will be B.
Hope it helps!
Watch the following video to Learn the Basics of Statistics
