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Finding the Fourth Proportional to 810.60, 1,118.98 and 664.80

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Solution

The fourth proportional to 810.60, 1,118.98 and 664.80 is: 917.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.60 : 1,118.98 = 664.80 : x
  2. Step 2: Convert to fraction form
    810.60/1,118.98 = 664.80/x
  3. Step 3: Cross multiply
    810.60x = 1,118.98 × 664.80
  4. Step 4: Simplify right side
    810.60x = 743,897.90
  5. Step 5: Solve for x
    x = 743,897.90/810.60
  6. Step 6: Final answer
    x = 917.71

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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.