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Finding the Fourth Proportional to 305.15, 420.32 and 284.99

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Solution

The fourth proportional to 305.15, 420.32 and 284.99 is: 392.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.15 : 420.32 = 284.99 : x
  2. Step 2: Convert to fraction form
    305.15/420.32 = 284.99/x
  3. Step 3: Cross multiply
    305.15x = 420.32 × 284.99
  4. Step 4: Simplify right side
    305.15x = 119,785.61
  5. Step 5: Solve for x
    x = 119,785.61/305.15
  6. Step 6: Final answer
    x = 392.55

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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.