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Finding the Fourth Proportional to 376.80, 518.40 and 355.20

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Solution

The fourth proportional to 376.80, 518.40 and 355.20 is: 488.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    376.80 : 518.40 = 355.20 : x
  2. Step 2: Convert to fraction form
    376.80/518.40 = 355.20/x
  3. Step 3: Cross multiply
    376.80x = 518.40 × 355.20
  4. Step 4: Simplify right side
    376.80x = 184,135.68
  5. Step 5: Solve for x
    x = 184,135.68/376.80
  6. Step 6: Final answer
    x = 488.68

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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.