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Finding the Fourth Proportional to 419.80, 621.52 and 419.80

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Solution

The fourth proportional to 419.80, 621.52 and 419.80 is: 621.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.80 : 621.52 = 419.80 : x
  2. Step 2: Convert to fraction form
    419.80/621.52 = 419.80/x
  3. Step 3: Cross multiply
    419.80x = 621.52 × 419.80
  4. Step 4: Simplify right side
    419.80x = 260,914.10
  5. Step 5: Solve for x
    x = 260,914.10/419.80
  6. Step 6: Final answer
    x = 621.52

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.