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Finding the Fourth Proportional to 511.90, 766.95 and 420.10

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Solution

The fourth proportional to 511.90, 766.95 and 420.10 is: 629.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.90 : 766.95 = 420.10 : x
  2. Step 2: Convert to fraction form
    511.90/766.95 = 420.10/x
  3. Step 3: Cross multiply
    511.90x = 766.95 × 420.10
  4. Step 4: Simplify right side
    511.90x = 322,195.70
  5. Step 5: Solve for x
    x = 322,195.70/511.90
  6. Step 6: Final answer
    x = 629.41

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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.