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Finding the Fourth Proportional to 399.60, 599.30 and 139.58

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Solution

The fourth proportional to 399.60, 599.30 and 139.58 is: 209.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.60 : 599.30 = 139.58 : x
  2. Step 2: Convert to fraction form
    399.60/599.30 = 139.58/x
  3. Step 3: Cross multiply
    399.60x = 599.30 × 139.58
  4. Step 4: Simplify right side
    399.60x = 83,650.29
  5. Step 5: Solve for x
    x = 83,650.29/399.60
  6. Step 6: Final answer
    x = 209.34

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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.