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Finding the Fourth Proportional to 409.86, 565.16 and 305.15

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Solution

The fourth proportional to 409.86, 565.16 and 305.15 is: 420.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.86 : 565.16 = 305.15 : x
  2. Step 2: Convert to fraction form
    409.86/565.16 = 305.15/x
  3. Step 3: Cross multiply
    409.86x = 565.16 × 305.15
  4. Step 4: Simplify right side
    409.86x = 172,454.22
  5. Step 5: Solve for x
    x = 172,454.22/409.86
  6. Step 6: Final answer
    x = 420.76

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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.