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Finding the Fourth Proportional to 305.16, 420.54 and 217.56

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Solution

The fourth proportional to 305.16, 420.54 and 217.56 is: 299.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.16 : 420.54 = 217.56 : x
  2. Step 2: Convert to fraction form
    305.16/420.54 = 217.56/x
  3. Step 3: Cross multiply
    305.16x = 420.54 × 217.56
  4. Step 4: Simplify right side
    305.16x = 91,492.68
  5. Step 5: Solve for x
    x = 91,492.68/305.16
  6. Step 6: Final answer
    x = 299.82

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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.