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Finding the Fourth Proportional to 412.79, 619.18 and 120.30

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Solution

The fourth proportional to 412.79, 619.18 and 120.30 is: 180.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.79 : 619.18 = 120.30 : x
  2. Step 2: Convert to fraction form
    412.79/619.18 = 120.30/x
  3. Step 3: Cross multiply
    412.79x = 619.18 × 120.30
  4. Step 4: Simplify right side
    412.79x = 74,487.35
  5. Step 5: Solve for x
    x = 74,487.35/412.79
  6. Step 6: Final answer
    x = 180.45

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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.