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Finding the Fourth Proportional to 629.93, 869.60 and 420.45

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Solution

The fourth proportional to 629.93, 869.60 and 420.45 is: 580.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.93 : 869.60 = 420.45 : x
  2. Step 2: Convert to fraction form
    629.93/869.60 = 420.45/x
  3. Step 3: Cross multiply
    629.93x = 869.60 × 420.45
  4. Step 4: Simplify right side
    629.93x = 365,621.22
  5. Step 5: Solve for x
    x = 365,621.22/629.93
  6. Step 6: Final answer
    x = 580.42

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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.