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Finding the Fourth Proportional to 399.78, 598.80 and 193.91

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Solution

The fourth proportional to 399.78, 598.80 and 193.91 is: 290.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.78 : 598.80 = 193.91 : x
  2. Step 2: Convert to fraction form
    399.78/598.80 = 193.91/x
  3. Step 3: Cross multiply
    399.78x = 598.80 × 193.91
  4. Step 4: Simplify right side
    399.78x = 116,115.81
  5. Step 5: Solve for x
    x = 116,115.81/399.78
  6. Step 6: Final answer
    x = 290.45

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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.