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Finding the Fourth Proportional to 419.30, 578.09 and 288.08

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Solution

The fourth proportional to 419.30, 578.09 and 288.08 is: 397.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.30 : 578.09 = 288.08 : x
  2. Step 2: Convert to fraction form
    419.30/578.09 = 288.08/x
  3. Step 3: Cross multiply
    419.30x = 578.09 × 288.08
  4. Step 4: Simplify right side
    419.30x = 166,533.28
  5. Step 5: Solve for x
    x = 166,533.28/419.30
  6. Step 6: Final answer
    x = 397.17

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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.