What is Mean Proportion?
If a and b be two numbers and c is mean proportional between a and b
Then,
a : c = c : b
Mean Proportion Example 1
Find the mean proportional between 25 and 100 ?
Explanation:
Let, the mean proportional between 25 and 100 be ‘ a ‘
25 : a :: a : 100
(Product of extremes = Product of means)
Here, Extremes are 25 and 100
Means are a and a
25 x 100 = a x a
a² = 25 x 100 = 2500
a = 50
Hence, the value of ‘a’ is 50
Mean Proportion Example 2
Find the mean proportional between 10 and 40 ?
Explanation:
Let, the mean proportional between 10 and 40 be ‘ a ‘
10 : a :: a : 40
(Product of extremes = Product of means)
Here, Extremes are 10 and 40
Means are a and a
10 x 40 = a x a
a² = 10 x 40 = 400
a = 20
Hence, the value of ‘a’ is 20
Mean Proportion Example 3
Find the mean proportional between 64 and 16 ?
Explanation:
Let, the mean proportional between 64 and 16 be ‘ a ‘
64 : a :: a : 16
(Product of extremes = Product of means)
Here, Extremes are 64 and 16
Means are a and a
64 x 16 = a x a
a² = 64 x 16 = 1024
a = 32
Hence, the value of ‘a’ is 32
Mean Proportion Example 4
Find the mean proportional between 9 and 4 ?
Explanation:
Let, the mean proportional between 9 and 4 be ‘ a ‘
9 : a :: a : 4
(Product of extremes = Product of means)
Here, Extremes are 9 and 4
Means are a and a
9 x 4 = a x a
a² = 9 x 4 = 36
a = 6
Hence, the value of ‘a’ is 6
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