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Finding the Fourth Proportional to 419.31, 628.65 and 328.20

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Solution

The fourth proportional to 419.31, 628.65 and 328.20 is: 492.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.31 : 628.65 = 328.20 : x
  2. Step 2: Convert to fraction form
    419.31/628.65 = 328.20/x
  3. Step 3: Cross multiply
    419.31x = 628.65 × 328.20
  4. Step 4: Simplify right side
    419.31x = 206,322.93
  5. Step 5: Solve for x
    x = 206,322.93/419.31
  6. Step 6: Final answer
    x = 492.05

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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.