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Finding the Fourth Proportional to 868.78, 1,303.19 and 406.31

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Solution

The fourth proportional to 868.78, 1,303.19 and 406.31 is: 609.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    868.78 : 1,303.19 = 406.31 : x
  2. Step 2: Convert to fraction form
    868.78/1,303.19 = 406.31/x
  3. Step 3: Cross multiply
    868.78x = 1,303.19 × 406.31
  4. Step 4: Simplify right side
    868.78x = 529,492.11
  5. Step 5: Solve for x
    x = 529,492.11/868.78
  6. Step 6: Final answer
    x = 609.47

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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.