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Finding the Fourth Proportional to 628.10, 940.80 and 339.20

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Solution

The fourth proportional to 628.10, 940.80 and 339.20 is: 508.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.10 : 940.80 = 339.20 : x
  2. Step 2: Convert to fraction form
    628.10/940.80 = 339.20/x
  3. Step 3: Cross multiply
    628.10x = 940.80 × 339.20
  4. Step 4: Simplify right side
    628.10x = 319,119.36
  5. Step 5: Solve for x
    x = 319,119.36/628.10
  6. Step 6: Final answer
    x = 508.07

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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.