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Finding the Fourth Proportional to 419.02, 628.20 and 288.70

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Solution

The fourth proportional to 419.02, 628.20 and 288.70 is: 432.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.02 : 628.20 = 288.70 : x
  2. Step 2: Convert to fraction form
    419.02/628.20 = 288.70/x
  3. Step 3: Cross multiply
    419.02x = 628.20 × 288.70
  4. Step 4: Simplify right side
    419.02x = 181,361.34
  5. Step 5: Solve for x
    x = 181,361.34/419.02
  6. Step 6: Final answer
    x = 432.82

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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.