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Finding the Fourth Proportional to 306.09, 421.45 and 256.86

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Solution

The fourth proportional to 306.09, 421.45 and 256.86 is: 353.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.09 : 421.45 = 256.86 : x
  2. Step 2: Convert to fraction form
    306.09/421.45 = 256.86/x
  3. Step 3: Cross multiply
    306.09x = 421.45 × 256.86
  4. Step 4: Simplify right side
    306.09x = 108,253.65
  5. Step 5: Solve for x
    x = 108,253.65/306.09
  6. Step 6: Final answer
    x = 353.67

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.