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Finding the Fourth Proportional to 840, 1,260.08 and 743.40

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Solution

The fourth proportional to 840, 1,260.08 and 743.40 is: 1,115.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    840 : 1,260.08 = 743.40 : x
  2. Step 2: Convert to fraction form
    840/1,260.08 = 743.40/x
  3. Step 3: Cross multiply
    840x = 1,260.08 × 743.40
  4. Step 4: Simplify right side
    840x = 936,743.47
  5. Step 5: Solve for x
    x = 936,743.47/840
  6. Step 6: Final answer
    x = 1,115.17

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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.