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Finding the Fourth Proportional to 500.31, 690.39 and 303.80

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Solution

The fourth proportional to 500.31, 690.39 and 303.80 is: 419.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.31 : 690.39 = 303.80 : x
  2. Step 2: Convert to fraction form
    500.31/690.39 = 303.80/x
  3. Step 3: Cross multiply
    500.31x = 690.39 × 303.80
  4. Step 4: Simplify right side
    500.31x = 209,737.03
  5. Step 5: Solve for x
    x = 209,737.03/500.31
  6. Step 6: Final answer
    x = 419.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.