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Finding the Fourth Proportional to 620.08, 928.16 and 389.20

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Solution

The fourth proportional to 620.08, 928.16 and 389.20 is: 582.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.08 : 928.16 = 389.20 : x
  2. Step 2: Convert to fraction form
    620.08/928.16 = 389.20/x
  3. Step 3: Cross multiply
    620.08x = 928.16 × 389.20
  4. Step 4: Simplify right side
    620.08x = 361,239.87
  5. Step 5: Solve for x
    x = 361,239.87/620.08
  6. Step 6: Final answer
    x = 582.57

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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.