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Finding the Fourth Proportional to 871.47, 1,307.52 and 438.30

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Solution

The fourth proportional to 871.47, 1,307.52 and 438.30 is: 657.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.47 : 1,307.52 = 438.30 : x
  2. Step 2: Convert to fraction form
    871.47/1,307.52 = 438.30/x
  3. Step 3: Cross multiply
    871.47x = 1,307.52 × 438.30
  4. Step 4: Simplify right side
    871.47x = 573,086.02
  5. Step 5: Solve for x
    x = 573,086.02/871.47
  6. Step 6: Final answer
    x = 657.61

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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.