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Finding the Fourth Proportional to 419.08, 579.02 and 288.40

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Solution

The fourth proportional to 419.08, 579.02 and 288.40 is: 398.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.08 : 579.02 = 288.40 : x
  2. Step 2: Convert to fraction form
    419.08/579.02 = 288.40/x
  3. Step 3: Cross multiply
    419.08x = 579.02 × 288.40
  4. Step 4: Simplify right side
    419.08x = 166,989.37
  5. Step 5: Solve for x
    x = 166,989.37/419.08
  6. Step 6: Final answer
    x = 398.47

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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.