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Finding the Fourth Proportional to 858.76, 1,288.13 and 209.49

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Solution

The fourth proportional to 858.76, 1,288.13 and 209.49 is: 314.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.76 : 1,288.13 = 209.49 : x
  2. Step 2: Convert to fraction form
    858.76/1,288.13 = 209.49/x
  3. Step 3: Cross multiply
    858.76x = 1,288.13 × 209.49
  4. Step 4: Simplify right side
    858.76x = 269,851.27
  5. Step 5: Solve for x
    x = 269,851.27/858.76
  6. Step 6: Final answer
    x = 314.24

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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.