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Question

The third proportional to 9 and 15 is:

This question was previously asked in
SSC GD 2018 Question Paper Hindi (09-Mar-2019) (Shift 1)
The correct answer is

25

Third Proportional Calculation for 9 and 15

To find the third proportional to two numbers, say a and b, we look for a number x such that the ratio a : b is the same as b : x. This can be written as:

$ a : b \:: b : x $

Or in fractional form:

$ \frac{a}{b} = \frac{b}{x} $

Calculating the Third Proportional

In this problem, we have a = 9 and b = 15. We need to find the third proportional, x.

Set up the proportion:

$ \frac{9}{15} = \frac{15}{x} $

To solve for x, we can cross-multiply:

$ 9 \times x = 15 \times 15 $

Calculate the product on the right side:

$ 9x = 225 $

Now, divide both sides by 9 to isolate x:

$ x = \frac{225}{9} $

$ x = 25 $

Result

The third proportional to 9 and 15 is 25.

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Similar Questions

  1. The average age of 3 persons is 30 years.If their ages are in the ratio of 3 : 5 : 7 respectively, then the age of the eldest person is:

  2. The income of A and B are in the ratio 5 : 3. The expenses of A, B and C are in the ratio of 8 : 5 : 2. If C spends 2000 and B saves ₹ 700, then A saves:

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Important Questions from Ratio and Proportion

  1. In a mixture of 156 litres, the ratio of milk and water is 7 : 6. How much water should be added to make the ratio 14 : 13?

  2. If the ratio of the first to second number is 3 : 4 and that of the second to the third number is 8 : 5, and sum of three numbers is 190 then the third number is:

  3. The average age of 3 persons is 30 years.If their ages are in the ratio of 3 : 5 : 7 respectively, then the age of the eldest person is:

  4. The income of A and B are in the ratio 5 : 3. The expenses of A, B and C are in the ratio of 8 : 5 : 2. If C spends 2000 and B saves ₹ 700, then A saves:

  5. If A : B = 2 : 3, B : C = 3 : 4 and C : D = 3 : 5 then value of A : B : C : D is:

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