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Finding the Fourth Proportional to 619.90, 930.30 and 414.40

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Solution

The fourth proportional to 619.90, 930.30 and 414.40 is: 621.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.90 : 930.30 = 414.40 : x
  2. Step 2: Convert to fraction form
    619.90/930.30 = 414.40/x
  3. Step 3: Cross multiply
    619.90x = 930.30 × 414.40
  4. Step 4: Simplify right side
    619.90x = 385,516.32
  5. Step 5: Solve for x
    x = 385,516.32/619.90
  6. Step 6: Final answer
    x = 621.90

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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.