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Finding the Fourth Proportional to 438.60, 657.69 and 256.05

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Solution

The fourth proportional to 438.60, 657.69 and 256.05 is: 383.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.60 : 657.69 = 256.05 : x
  2. Step 2: Convert to fraction form
    438.60/657.69 = 256.05/x
  3. Step 3: Cross multiply
    438.60x = 657.69 × 256.05
  4. Step 4: Simplify right side
    438.60x = 168,401.52
  5. Step 5: Solve for x
    x = 168,401.52/438.60
  6. Step 6: Final answer
    x = 383.95

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.