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Finding the Fourth Proportional to 369, 509.10 and 221.58

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Solution

The fourth proportional to 369, 509.10 and 221.58 is: 305.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    369 : 509.10 = 221.58 : x
  2. Step 2: Convert to fraction form
    369/509.10 = 221.58/x
  3. Step 3: Cross multiply
    369x = 509.10 × 221.58
  4. Step 4: Simplify right side
    369x = 112,806.38
  5. Step 5: Solve for x
    x = 112,806.38/369
  6. Step 6: Final answer
    x = 305.71

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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.