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Finding the Fourth Proportional to 125.00, 172.61 and 78.45

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Solution

The fourth proportional to 125.00, 172.61 and 78.45 is: 108.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    125.00 : 172.61 = 78.45 : x
  2. Step 2: Convert to fraction form
    125.00/172.61 = 78.45/x
  3. Step 3: Cross multiply
    125.00x = 172.61 × 78.45
  4. Step 4: Simplify right side
    125.00x = 13,542.10
  5. Step 5: Solve for x
    x = 13,542.10/125.00
  6. Step 6: Final answer
    x = 108.33

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.