To find third proportional of any two numbers let say a and b be two numbers and c is in third proportion with a and b
Then,
a : b = b : c
Third Proportional Example 1
Find the third proportion to 6 and 12?
Explanation:
To find third proportional of any two numbers let say a and b be two numbers and c is in third proportion with a and b
Then,
a : b = b : c
Let, the third proportion to 6 and 12 be a
6 : 12 :: 12 : a
(Product of Extremes= Product of Means)
Here, Extremes are= 6 and a
Means are = 12 and 12
6 x a = 12 x 12
a = (12 x 12)/6 = 24
Hence, the value of ‘a’ is 24
Third Proportional Example 2
Find the third proportion to 8 and 16?
Explanation:
To find third proportional of any two numbers let say a and b be two numbers and c is in third proportion with a and b
Then,
a : b = b : c
Let, the third proportion to 8 and 16 be a
8 : 16 :: 16 : a
(Product of Extremes= Product of Means)
Here, Extremes are= 8 and a
Means are = 16 and 16
8 x a = 16 x 16
a = (16 x 16)/8 = 32
Hence, the value of ‘a’ is 32
Third Proportional Example 3
Find the third proportion to 16 and 24?
Explanation:
To find third proportional of any two numbers let say a and b be two numbers and c is in third proportion with a and b
Then,
a : b = b : c
Let, the third proportion to 16 and 24 be a
16 : 24 :: 24 : a
(Product of Extremes= Product of Means)
Here, Extremes are= 16 and a
Means are = 24 and 24
16 x a = 24 x 24
a = (24 x 24)/16Â = 36
Hence, the value of ‘a’ is 36
Third Proportional Example 4
Find the third proportion to 5 and 25?
Explanation:
To find third proportional of any two numbers let say a and b be two numbers and c is in third proportion with a and b
Then,
a : b = b : c
Let, the third proportion to 5 and 25 be a
5 : 25 :: 25 : a
(Product of Extremes= Product of Means)
Here, Extremes are= 5 and a
Means are = 25 and 25
5 x a = 25 x 25
a = (25 x 25)/5 = 125
Hence, the value of ‘a’ is 125
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