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Finding the Fourth Proportional to 619.92, 928.40 and 402.80

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Solution

The fourth proportional to 619.92, 928.40 and 402.80 is: 603.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.92 : 928.40 = 402.80 : x
  2. Step 2: Convert to fraction form
    619.92/928.40 = 402.80/x
  3. Step 3: Cross multiply
    619.92x = 928.40 × 402.80
  4. Step 4: Simplify right side
    619.92x = 373,959.52
  5. Step 5: Solve for x
    x = 373,959.52/619.92
  6. Step 6: Final answer
    x = 603.24

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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.