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Finding the Fourth Proportional to 438.55, 657.83 and 256.30

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Solution

The fourth proportional to 438.55, 657.83 and 256.30 is: 384.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.55 : 657.83 = 256.30 : x
  2. Step 2: Convert to fraction form
    438.55/657.83 = 256.30/x
  3. Step 3: Cross multiply
    438.55x = 657.83 × 256.30
  4. Step 4: Simplify right side
    438.55x = 168,600.55
  5. Step 5: Solve for x
    x = 168,600.55/438.55
  6. Step 6: Final answer
    x = 384.45

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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.