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Finding the Fourth Proportional to 879.78, 1,320.48 and 555.78

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Solution

The fourth proportional to 879.78, 1,320.48 and 555.78 is: 834.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.78 : 1,320.48 = 555.78 : x
  2. Step 2: Convert to fraction form
    879.78/1,320.48 = 555.78/x
  3. Step 3: Cross multiply
    879.78x = 1,320.48 × 555.78
  4. Step 4: Simplify right side
    879.78x = 733,896.37
  5. Step 5: Solve for x
    x = 733,896.37/879.78
  6. Step 6: Final answer
    x = 834.18

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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.