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Finding the Fourth Proportional to 369.09, 509.28 and 221.70

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Solution

The fourth proportional to 369.09, 509.28 and 221.70 is: 305.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    369.09 : 509.28 = 221.70 : x
  2. Step 2: Convert to fraction form
    369.09/509.28 = 221.70/x
  3. Step 3: Cross multiply
    369.09x = 509.28 × 221.70
  4. Step 4: Simplify right side
    369.09x = 112,907.38
  5. Step 5: Solve for x
    x = 112,907.38/369.09
  6. Step 6: Final answer
    x = 305.91

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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.