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Finding the Fourth Proportional to 428.08, 642.90 and 410.68

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Solution

The fourth proportional to 428.08, 642.90 and 410.68 is: 616.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.08 : 642.90 = 410.68 : x
  2. Step 2: Convert to fraction form
    428.08/642.90 = 410.68/x
  3. Step 3: Cross multiply
    428.08x = 642.90 × 410.68
  4. Step 4: Simplify right side
    428.08x = 264,026.17
  5. Step 5: Solve for x
    x = 264,026.17/428.08
  6. Step 6: Final answer
    x = 616.77

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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.