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Finding the Fourth Proportional to 256.72, 384.80 and 102.61

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Solution

The fourth proportional to 256.72, 384.80 and 102.61 is: 153.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.72 : 384.80 = 102.61 : x
  2. Step 2: Convert to fraction form
    256.72/384.80 = 102.61/x
  3. Step 3: Cross multiply
    256.72x = 384.80 × 102.61
  4. Step 4: Simplify right side
    256.72x = 39,483.81
  5. Step 5: Solve for x
    x = 39,483.81/256.72
  6. Step 6: Final answer
    x = 153.80

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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.