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Finding the Fourth Proportional to 515.38, 711.35 and 305.59

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Solution

The fourth proportional to 515.38, 711.35 and 305.59 is: 421.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.38 : 711.35 = 305.59 : x
  2. Step 2: Convert to fraction form
    515.38/711.35 = 305.59/x
  3. Step 3: Cross multiply
    515.38x = 711.35 × 305.59
  4. Step 4: Simplify right side
    515.38x = 217,381.45
  5. Step 5: Solve for x
    x = 217,381.45/515.38
  6. Step 6: Final answer
    x = 421.79

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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.