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Finding the Fourth Proportional to 515.07, 710.85 and 305.31

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Solution

The fourth proportional to 515.07, 710.85 and 305.31 is: 421.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.07 : 710.85 = 305.31 : x
  2. Step 2: Convert to fraction form
    515.07/710.85 = 305.31/x
  3. Step 3: Cross multiply
    515.07x = 710.85 × 305.31
  4. Step 4: Simplify right side
    515.07x = 217,029.61
  5. Step 5: Solve for x
    x = 217,029.61/515.07
  6. Step 6: Final answer
    x = 421.36

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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.