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Finding the Fourth Proportional to 305.58, 420.85 and 284.06

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Solution

The fourth proportional to 305.58, 420.85 and 284.06 is: 391.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.58 : 420.85 = 284.06 : x
  2. Step 2: Convert to fraction form
    305.58/420.85 = 284.06/x
  3. Step 3: Cross multiply
    305.58x = 420.85 × 284.06
  4. Step 4: Simplify right side
    305.58x = 119,546.49
  5. Step 5: Solve for x
    x = 119,546.49/305.58
  6. Step 6: Final answer
    x = 391.21

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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.