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Finding the Fourth Proportional to 511.80, 767.78 and 306.20

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Solution

The fourth proportional to 511.80, 767.78 and 306.20 is: 459.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.80 : 767.78 = 306.20 : x
  2. Step 2: Convert to fraction form
    511.80/767.78 = 306.20/x
  3. Step 3: Cross multiply
    511.80x = 767.78 × 306.20
  4. Step 4: Simplify right side
    511.80x = 235,088.87
  5. Step 5: Solve for x
    x = 235,088.87/511.80
  6. Step 6: Final answer
    x = 459.34

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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.