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Finding the Fourth Proportional to 813.37, 1,218.30 and 505.30

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Solution

The fourth proportional to 813.37, 1,218.30 and 505.30 is: 756.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.37 : 1,218.30 = 505.30 : x
  2. Step 2: Convert to fraction form
    813.37/1,218.30 = 505.30/x
  3. Step 3: Cross multiply
    813.37x = 1,218.30 × 505.30
  4. Step 4: Simplify right side
    813.37x = 615,606.99
  5. Step 5: Solve for x
    x = 615,606.99/813.37
  6. Step 6: Final answer
    x = 756.86

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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.