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Finding the Fourth Proportional to 807.78, 1,211.74 and 288.07

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Solution

The fourth proportional to 807.78, 1,211.74 and 288.07 is: 432.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.78 : 1,211.74 = 288.07 : x
  2. Step 2: Convert to fraction form
    807.78/1,211.74 = 288.07/x
  3. Step 3: Cross multiply
    807.78x = 1,211.74 × 288.07
  4. Step 4: Simplify right side
    807.78x = 349,065.94
  5. Step 5: Solve for x
    x = 349,065.94/807.78
  6. Step 6: Final answer
    x = 432.13

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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.