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Finding the Fourth Proportional to 399.45, 599.14 and 139.35

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Solution

The fourth proportional to 399.45, 599.14 and 139.35 is: 209.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.45 : 599.14 = 139.35 : x
  2. Step 2: Convert to fraction form
    399.45/599.14 = 139.35/x
  3. Step 3: Cross multiply
    399.45x = 599.14 × 139.35
  4. Step 4: Simplify right side
    399.45x = 83,490.16
  5. Step 5: Solve for x
    x = 83,490.16/399.45
  6. Step 6: Final answer
    x = 209.01

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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.