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Finding the Fourth Proportional to 429.60, 643.41 and 266.79

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Solution

The fourth proportional to 429.60, 643.41 and 266.79 is: 399.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.60 : 643.41 = 266.79 : x
  2. Step 2: Convert to fraction form
    429.60/643.41 = 266.79/x
  3. Step 3: Cross multiply
    429.60x = 643.41 × 266.79
  4. Step 4: Simplify right side
    429.60x = 171,655.35
  5. Step 5: Solve for x
    x = 171,655.35/429.60
  6. Step 6: Final answer
    x = 399.57

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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.