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Finding the Fourth Proportional to 369.10, 509.15 and 221.65

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Solution

The fourth proportional to 369.10, 509.15 and 221.65 is: 305.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    369.10 : 509.15 = 221.65 : x
  2. Step 2: Convert to fraction form
    369.10/509.15 = 221.65/x
  3. Step 3: Cross multiply
    369.10x = 509.15 × 221.65
  4. Step 4: Simplify right side
    369.10x = 112,853.10
  5. Step 5: Solve for x
    x = 112,853.10/369.10
  6. Step 6: Final answer
    x = 305.75

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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.