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Finding the Fourth Proportional to 401.19, 553.39 and 307.80

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Solution

The fourth proportional to 401.19, 553.39 and 307.80 is: 424.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.19 : 553.39 = 307.80 : x
  2. Step 2: Convert to fraction form
    401.19/553.39 = 307.80/x
  3. Step 3: Cross multiply
    401.19x = 553.39 × 307.80
  4. Step 4: Simplify right side
    401.19x = 170,330.68
  5. Step 5: Solve for x
    x = 170,330.68/401.19
  6. Step 6: Final answer
    x = 424.56

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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.