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Finding the Fourth Proportional to 501.10, 691.49 and 280

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Solution

The fourth proportional to 501.10, 691.49 and 280 is: 386.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.10 : 691.49 = 280 : x
  2. Step 2: Convert to fraction form
    501.10/691.49 = 280/x
  3. Step 3: Cross multiply
    501.10x = 691.49 × 280
  4. Step 4: Simplify right side
    501.10x = 193,615.80
  5. Step 5: Solve for x
    x = 193,615.80/501.10
  6. Step 6: Final answer
    x = 386.39

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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.