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Finding the Fourth Proportional to 209.03, 313.57 and 78.99

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Solution

The fourth proportional to 209.03, 313.57 and 78.99 is: 118.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.03 : 313.57 = 78.99 : x
  2. Step 2: Convert to fraction form
    209.03/313.57 = 78.99/x
  3. Step 3: Cross multiply
    209.03x = 313.57 × 78.99
  4. Step 4: Simplify right side
    209.03x = 24,768.70
  5. Step 5: Solve for x
    x = 24,768.70/209.03
  6. Step 6: Final answer
    x = 118.50

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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.