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Finding the Fourth Proportional to 416.80, 624.99 and 128.20

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Solution

The fourth proportional to 416.80, 624.99 and 128.20 is: 192.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    416.80 : 624.99 = 128.20 : x
  2. Step 2: Convert to fraction form
    416.80/624.99 = 128.20/x
  3. Step 3: Cross multiply
    416.80x = 624.99 × 128.20
  4. Step 4: Simplify right side
    416.80x = 80,123.72
  5. Step 5: Solve for x
    x = 80,123.72/416.80
  6. Step 6: Final answer
    x = 192.24

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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.