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Finding the Fourth Proportional to 807.61, 1,210.64 and 259.40

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Solution

The fourth proportional to 807.61, 1,210.64 and 259.40 is: 388.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.61 : 1,210.64 = 259.40 : x
  2. Step 2: Convert to fraction form
    807.61/1,210.64 = 259.40/x
  3. Step 3: Cross multiply
    807.61x = 1,210.64 × 259.40
  4. Step 4: Simplify right side
    807.61x = 314,040.02
  5. Step 5: Solve for x
    x = 314,040.02/807.61
  6. Step 6: Final answer
    x = 388.85

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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.