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Finding the Fourth Proportional to 503.40, 693.78 and 378.60

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Solution

The fourth proportional to 503.40, 693.78 and 378.60 is: 521.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    503.40 : 693.78 = 378.60 : x
  2. Step 2: Convert to fraction form
    503.40/693.78 = 378.60/x
  3. Step 3: Cross multiply
    503.40x = 693.78 × 378.60
  4. Step 4: Simplify right side
    503.40x = 262,665.11
  5. Step 5: Solve for x
    x = 262,665.11/503.40
  6. Step 6: Final answer
    x = 521.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.