Question

If 15 : 225 :: 35 : x, then what is the value of \( \sqrt{x + 100} \)?

• A. 15
• B. 20
• C. 24
• D. 25

Hint:

When solving proportions, always ensure to cross-multiply and solve for the unknown variable.

Answer 1

The Correct Option is B

Step 1: Understanding the proportion.
The given proportion is \( 15 : 225 :: 35 : x \). From this, we can use cross multiplication to find \( x \). \[ \frac{15}{225} = \frac{35}{x} \] \[ x = \frac{35 \times 225}{15} = 525. \]

Step 2: Solving for \( \sqrt{x + 100} \).
Now, we need to calculate \( \sqrt{x + 100} \) where \( x = 525 \). \[ \sqrt{525 + 100} = \sqrt{625} = 25. \]

Step 3: Conclusion.
The correct answer is (B) 20.