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Finding the Fourth Proportional to 903.72, 1,355.72 and 287.31

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Solution

The fourth proportional to 903.72, 1,355.72 and 287.31 is: 431.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    903.72 : 1,355.72 = 287.31 : x
  2. Step 2: Convert to fraction form
    903.72/1,355.72 = 287.31/x
  3. Step 3: Cross multiply
    903.72x = 1,355.72 × 287.31
  4. Step 4: Simplify right side
    903.72x = 389,511.91
  5. Step 5: Solve for x
    x = 389,511.91/903.72
  6. Step 6: Final answer
    x = 431.01

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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.