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Finding the Fourth Proportional to 807.60, 1,211.57 and 287.63

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Solution

The fourth proportional to 807.60, 1,211.57 and 287.63 is: 431.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.60 : 1,211.57 = 287.63 : x
  2. Step 2: Convert to fraction form
    807.60/1,211.57 = 287.63/x
  3. Step 3: Cross multiply
    807.60x = 1,211.57 × 287.63
  4. Step 4: Simplify right side
    807.60x = 348,483.88
  5. Step 5: Solve for x
    x = 348,483.88/807.60
  6. Step 6: Final answer
    x = 431.51

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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.