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Finding the Fourth Proportional to 801.90, 1,105.65 and 615.60

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Solution

The fourth proportional to 801.90, 1,105.65 and 615.60 is: 848.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.90 : 1,105.65 = 615.60 : x
  2. Step 2: Convert to fraction form
    801.90/1,105.65 = 615.60/x
  3. Step 3: Cross multiply
    801.90x = 1,105.65 × 615.60
  4. Step 4: Simplify right side
    801.90x = 680,638.14
  5. Step 5: Solve for x
    x = 680,638.14/801.90
  6. Step 6: Final answer
    x = 848.78

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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.