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Finding the Fourth Proportional to 842.85, 1,264.05 and 287.55

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Solution

The fourth proportional to 842.85, 1,264.05 and 287.55 is: 431.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    842.85 : 1,264.05 = 287.55 : x
  2. Step 2: Convert to fraction form
    842.85/1,264.05 = 287.55/x
  3. Step 3: Cross multiply
    842.85x = 1,264.05 × 287.55
  4. Step 4: Simplify right side
    842.85x = 363,477.58
  5. Step 5: Solve for x
    x = 363,477.58/842.85
  6. Step 6: Final answer
    x = 431.25

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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.