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Finding the Fourth Proportional to 430.08, 645.12 and 285.36

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Solution

The fourth proportional to 430.08, 645.12 and 285.36 is: 428.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.08 : 645.12 = 285.36 : x
  2. Step 2: Convert to fraction form
    430.08/645.12 = 285.36/x
  3. Step 3: Cross multiply
    430.08x = 645.12 × 285.36
  4. Step 4: Simplify right side
    430.08x = 184,091.44
  5. Step 5: Solve for x
    x = 184,091.44/430.08
  6. Step 6: Final answer
    x = 428.04

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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.