1

Problem

Find the third proportion to 10,5.

2

Step

Let us take the third proportion is

x

3

Step

We can write the above numbers in the proportional form (a :b::b :c):

10 : 5::5 : x

4

Formula

Hint: \$a/b::b/c\$.

5

Hint

Here a = 10 , b = 5 ,c = x.

6

Step

Let us find the x value:

x = \$ (5 \times 5)/(10)\$

x = 2.5

7

Solution

So, the third proportion is x = 2.5.

8

Sumup

Please summarize steps

Choices

9

Choice-A

This is incorrect because it doesn’t satisfy the proportionality

Correct 2.5

10

Choice-B

This is the correct third proportion because it satisfies the proportion

Wrong $1.50

11

Choice-C

This is incorrect because it is equal to the second term (b), not the third proportion

Wrong $5.00

12

Choice-D

This is incorrect because it is equal to the first term (a), not the third proportion

Wrong $10.00

13

Answer

Option

A

14

Sumup

Please summarize choices