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Finding the Fourth Proportional to 505.15, 757.75 and 139.95

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Solution

The fourth proportional to 505.15, 757.75 and 139.95 is: 209.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.15 : 757.75 = 139.95 : x
  2. Step 2: Convert to fraction form
    505.15/757.75 = 139.95/x
  3. Step 3: Cross multiply
    505.15x = 757.75 × 139.95
  4. Step 4: Simplify right side
    505.15x = 106,047.11
  5. Step 5: Solve for x
    x = 106,047.11/505.15
  6. Step 6: Final answer
    x = 209.93

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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.