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Finding the Fourth Proportional to 429.40, 643.71 and 275.37

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Solution

The fourth proportional to 429.40, 643.71 and 275.37 is: 412.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.40 : 643.71 = 275.37 : x
  2. Step 2: Convert to fraction form
    429.40/643.71 = 275.37/x
  3. Step 3: Cross multiply
    429.40x = 643.71 × 275.37
  4. Step 4: Simplify right side
    429.40x = 177,258.42
  5. Step 5: Solve for x
    x = 177,258.42/429.40
  6. Step 6: Final answer
    x = 412.81

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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.