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Finding the Fourth Proportional to 879.86, 1,320 and 490.25

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Solution

The fourth proportional to 879.86, 1,320 and 490.25 is: 735.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.86 : 1,320 = 490.25 : x
  2. Step 2: Convert to fraction form
    879.86/1,320 = 490.25/x
  3. Step 3: Cross multiply
    879.86x = 1,320 × 490.25
  4. Step 4: Simplify right side
    879.86x = 647,130
  5. Step 5: Solve for x
    x = 647,130/879.86
  6. Step 6: Final answer
    x = 735.49

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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.