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Finding the Fourth Proportional to 409.95, 615.32 and 319.64

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Solution

The fourth proportional to 409.95, 615.32 and 319.64 is: 479.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.95 : 615.32 = 319.64 : x
  2. Step 2: Convert to fraction form
    409.95/615.32 = 319.64/x
  3. Step 3: Cross multiply
    409.95x = 615.32 × 319.64
  4. Step 4: Simplify right side
    409.95x = 196,676.21
  5. Step 5: Solve for x
    x = 196,676.21/409.95
  6. Step 6: Final answer
    x = 479.76

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.