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Finding the Fourth Proportional to 509.85, 759.71 and 485.05

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Solution

The fourth proportional to 509.85, 759.71 and 485.05 is: 722.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.85 : 759.71 = 485.05 : x
  2. Step 2: Convert to fraction form
    509.85/759.71 = 485.05/x
  3. Step 3: Cross multiply
    509.85x = 759.71 × 485.05
  4. Step 4: Simplify right side
    509.85x = 368,498.70
  5. Step 5: Solve for x
    x = 368,498.70/509.85
  6. Step 6: Final answer
    x = 722.76

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.