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Finding the Fourth Proportional to 840.24, 1,260.78 and 511.24

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Solution

The fourth proportional to 840.24, 1,260.78 and 511.24 is: 767.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.24 : 1,260.78 = 511.24 : x
  2. Step 2: Convert to fraction form
    840.24/1,260.78 = 511.24/x
  3. Step 3: Cross multiply
    840.24x = 1,260.78 × 511.24
  4. Step 4: Simplify right side
    840.24x = 644,561.17
  5. Step 5: Solve for x
    x = 644,561.17/840.24
  6. Step 6: Final answer
    x = 767.12

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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.