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Finding the Fourth Proportional to 903.56, 1,355.20 and 287.30

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Solution

The fourth proportional to 903.56, 1,355.20 and 287.30 is: 430.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    903.56 : 1,355.20 = 287.30 : x
  2. Step 2: Convert to fraction form
    903.56/1,355.20 = 287.30/x
  3. Step 3: Cross multiply
    903.56x = 1,355.20 × 287.30
  4. Step 4: Simplify right side
    903.56x = 389,351.63
  5. Step 5: Solve for x
    x = 389,351.63/903.56
  6. Step 6: Final answer
    x = 430.91

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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.