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Finding the Fourth Proportional to 370.60, 555.95 and 139.78

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Solution

The fourth proportional to 370.60, 555.95 and 139.78 is: 209.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    370.60 : 555.95 = 139.78 : x
  2. Step 2: Convert to fraction form
    370.60/555.95 = 139.78/x
  3. Step 3: Cross multiply
    370.60x = 555.95 × 139.78
  4. Step 4: Simplify right side
    370.60x = 77,710.69
  5. Step 5: Solve for x
    x = 77,710.69/370.60
  6. Step 6: Final answer
    x = 209.69

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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.