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Finding the Fourth Proportional to 401.99, 602.89 and 128.10

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Solution

The fourth proportional to 401.99, 602.89 and 128.10 is: 192.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.99 : 602.89 = 128.10 : x
  2. Step 2: Convert to fraction form
    401.99/602.89 = 128.10/x
  3. Step 3: Cross multiply
    401.99x = 602.89 × 128.10
  4. Step 4: Simplify right side
    401.99x = 77,229.57
  5. Step 5: Solve for x
    x = 77,229.57/401.99
  6. Step 6: Final answer
    x = 192.12

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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.