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Finding the Fourth Proportional to 511.80, 766.28 and 421.58

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Solution

The fourth proportional to 511.80, 766.28 and 421.58 is: 631.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.80 : 766.28 = 421.58 : x
  2. Step 2: Convert to fraction form
    511.80/766.28 = 421.58/x
  3. Step 3: Cross multiply
    511.80x = 766.28 × 421.58
  4. Step 4: Simplify right side
    511.80x = 323,048.32
  5. Step 5: Solve for x
    x = 323,048.32/511.80
  6. Step 6: Final answer
    x = 631.20

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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.