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Finding the Fourth Proportional to 429.68, 643.44 and 307.76

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Solution

The fourth proportional to 429.68, 643.44 and 307.76 is: 460.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.68 : 643.44 = 307.76 : x
  2. Step 2: Convert to fraction form
    429.68/643.44 = 307.76/x
  3. Step 3: Cross multiply
    429.68x = 643.44 × 307.76
  4. Step 4: Simplify right side
    429.68x = 198,025.09
  5. Step 5: Solve for x
    x = 198,025.09/429.68
  6. Step 6: Final answer
    x = 460.87

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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.