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Finding the Fourth Proportional to 511.10, 766.65 and 485.90

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Solution

The fourth proportional to 511.10, 766.65 and 485.90 is: 728.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.10 : 766.65 = 485.90 : x
  2. Step 2: Convert to fraction form
    511.10/766.65 = 485.90/x
  3. Step 3: Cross multiply
    511.10x = 766.65 × 485.90
  4. Step 4: Simplify right side
    511.10x = 372,515.24
  5. Step 5: Solve for x
    x = 372,515.24/511.10
  6. Step 6: Final answer
    x = 728.85

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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.