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Finding the Fourth Proportional to 418.95, 578.35 and 279.30

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Solution

The fourth proportional to 418.95, 578.35 and 279.30 is: 385.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.95 : 578.35 = 279.30 : x
  2. Step 2: Convert to fraction form
    418.95/578.35 = 279.30/x
  3. Step 3: Cross multiply
    418.95x = 578.35 × 279.30
  4. Step 4: Simplify right side
    418.95x = 161,528.87
  5. Step 5: Solve for x
    x = 161,528.87/418.95
  6. Step 6: Final answer
    x = 385.56

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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.