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Finding the Fourth Proportional to 714.86, 986.28 and 490.80

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Solution

The fourth proportional to 714.86, 986.28 and 490.80 is: 677.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    714.86 : 986.28 = 490.80 : x
  2. Step 2: Convert to fraction form
    714.86/986.28 = 490.80/x
  3. Step 3: Cross multiply
    714.86x = 986.28 × 490.80
  4. Step 4: Simplify right side
    714.86x = 484,066.22
  5. Step 5: Solve for x
    x = 484,066.22/714.86
  6. Step 6: Final answer
    x = 677.15

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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.