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Finding the Fourth Proportional to 629.86, 869.06 and 419.80

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Solution

The fourth proportional to 629.86, 869.06 and 419.80 is: 579.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.86 : 869.06 = 419.80 : x
  2. Step 2: Convert to fraction form
    629.86/869.06 = 419.80/x
  3. Step 3: Cross multiply
    629.86x = 869.06 × 419.80
  4. Step 4: Simplify right side
    629.86x = 364,831.39
  5. Step 5: Solve for x
    x = 364,831.39/629.86
  6. Step 6: Final answer
    x = 579.23

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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.