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Finding the Fourth Proportional to 401.80, 557.02 and 379.90

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Solution

The fourth proportional to 401.80, 557.02 and 379.90 is: 526.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.80 : 557.02 = 379.90 : x
  2. Step 2: Convert to fraction form
    401.80/557.02 = 379.90/x
  3. Step 3: Cross multiply
    401.80x = 557.02 × 379.90
  4. Step 4: Simplify right side
    401.80x = 211,611.90
  5. Step 5: Solve for x
    x = 211,611.90/401.80
  6. Step 6: Final answer
    x = 526.66

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.