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Finding the Fourth Proportional to 502.21, 752.35 and 420.09

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Solution

The fourth proportional to 502.21, 752.35 and 420.09 is: 629.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    502.21 : 752.35 = 420.09 : x
  2. Step 2: Convert to fraction form
    502.21/752.35 = 420.09/x
  3. Step 3: Cross multiply
    502.21x = 752.35 × 420.09
  4. Step 4: Simplify right side
    502.21x = 316,052.22
  5. Step 5: Solve for x
    x = 316,052.22/502.21
  6. Step 6: Final answer
    x = 629.32

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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.