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Finding the Fourth Proportional to 807.13, 1,210.85 and 287.18

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Solution

The fourth proportional to 807.13, 1,210.85 and 287.18 is: 430.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.13 : 1,210.85 = 287.18 : x
  2. Step 2: Convert to fraction form
    807.13/1,210.85 = 287.18/x
  3. Step 3: Cross multiply
    807.13x = 1,210.85 × 287.18
  4. Step 4: Simplify right side
    807.13x = 347,730.03
  5. Step 5: Solve for x
    x = 347,730.03/807.13
  6. Step 6: Final answer
    x = 430.82

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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.