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Finding the Fourth Proportional to 491.06, 736.78 and 285.78

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Solution

The fourth proportional to 491.06, 736.78 and 285.78 is: 428.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.06 : 736.78 = 285.78 : x
  2. Step 2: Convert to fraction form
    491.06/736.78 = 285.78/x
  3. Step 3: Cross multiply
    491.06x = 736.78 × 285.78
  4. Step 4: Simplify right side
    491.06x = 210,556.99
  5. Step 5: Solve for x
    x = 210,556.99/491.06
  6. Step 6: Final answer
    x = 428.78

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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.