Answer: Option A. -> 18

Answer: Option D. -> 4

Solution: The third proportional to two given numbers is the number which is in the same ratio as the other two numbers. This number is found by solving a particular equation.

Definition: The third proportional to two given numbers is a number which is in the same ratio as the other two numbers.

Formula: The formula for finding the third proportional to two given numbers a and b is given by:

a:b = c:x

where x is the third proportional to a and b.

In this question, the two given numbers are 1 and 2.

Therefore, the equation becomes:

1:2 = c:x

Here, c is a constant and x is the third proportional to 1 and 2.

Solving the equation, we get:

1x = 2c

x = 2c

Since c is a constant,

x = 2

Therefore, the third proportional to 1 and 2 is 4.

Hence, the correct answer is Option D. 4.

If you think the solution is wrong then please provide your own solution below in the comments section .

Answer: Option B. -> 21
The fourth proportional to 12, 14 and 18 can be found by using the formula of proportion. In mathematics, proportion refers to the equality of ratios, i.e., two or more quantities are proportional if their ratio is equal.
A proportion can be written in the form of a:b = c:d where a, b, c, and d are any four numbers. The fourth proportional to a, b and c can be found using the following formula:
d = (b * c) / a
Now, let's apply the formula to find the fourth proportional to 12, 14 and 18:
Given, a = 12, b = 14 and c = 18
So, d = (b * c) / a= (14 * 18) / 12= 21
Hence, the fourth proportional to 12, 14 and 18 is 21. So, the correct option is B.
Let's summarize the solution in bullet points:

• Proportion refers to the equality of ratios
• The formula to find the fourth proportional is d = (b * c) / a
• Given, a = 12, b = 14 and c = 18
• Applying the formula, d = (14 * 18) / 12 = 21
• Hence, the fourth proportional to 12, 14 and 18 is 21.

Therefore, the correct option is B.

Answer: Option C. -> 6

Answer: Option A. -> 2

Answer: Option D. -> \(4\frac{1}{6}\)

Answer: Option A. -> 2 : 3 : 4 : 5

Answer: Option C. -> 375

Answer: Option C. -> 3 : 4 : 6

Answer: Option C. -> 8 : 4 : 3