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Finding the Fourth Proportional to 419.02, 628.71 and 145.31

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Solution

The fourth proportional to 419.02, 628.71 and 145.31 is: 218.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.02 : 628.71 = 145.31 : x
  2. Step 2: Convert to fraction form
    419.02/628.71 = 145.31/x
  3. Step 3: Cross multiply
    419.02x = 628.71 × 145.31
  4. Step 4: Simplify right side
    419.02x = 91,357.85
  5. Step 5: Solve for x
    x = 91,357.85/419.02
  6. Step 6: Final answer
    x = 218.03

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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.