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Finding the Fourth Proportional to 429.64, 641.35 and 399.64

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Solution

The fourth proportional to 429.64, 641.35 and 399.64 is: 596.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.64 : 641.35 = 399.64 : x
  2. Step 2: Convert to fraction form
    429.64/641.35 = 399.64/x
  3. Step 3: Cross multiply
    429.64x = 641.35 × 399.64
  4. Step 4: Simplify right side
    429.64x = 256,309.11
  5. Step 5: Solve for x
    x = 256,309.11/429.64
  6. Step 6: Final answer
    x = 596.57

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.