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Finding the Fourth Proportional to 511.20, 766.80 and 457.20

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Solution

The fourth proportional to 511.20, 766.80 and 457.20 is: 685.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.20 : 766.80 = 457.20 : x
  2. Step 2: Convert to fraction form
    511.20/766.80 = 457.20/x
  3. Step 3: Cross multiply
    511.20x = 766.80 × 457.20
  4. Step 4: Simplify right side
    511.20x = 350,580.96
  5. Step 5: Solve for x
    x = 350,580.96/511.20
  6. Step 6: Final answer
    x = 685.80

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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.