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Finding the Fourth Proportional to 726.90, 1,003.10 and 428.18

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Solution

The fourth proportional to 726.90, 1,003.10 and 428.18 is: 590.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    726.90 : 1,003.10 = 428.18 : x
  2. Step 2: Convert to fraction form
    726.90/1,003.10 = 428.18/x
  3. Step 3: Cross multiply
    726.90x = 1,003.10 × 428.18
  4. Step 4: Simplify right side
    726.90x = 429,501.27
  5. Step 5: Solve for x
    x = 429,501.27/726.90
  6. Step 6: Final answer
    x = 590.87

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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.