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Finding the Fourth Proportional to 511.21, 705 and 491.23

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Solution

The fourth proportional to 511.21, 705 and 491.23 is: 677.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.21 : 705 = 491.23 : x
  2. Step 2: Convert to fraction form
    511.21/705 = 491.23/x
  3. Step 3: Cross multiply
    511.21x = 705 × 491.23
  4. Step 4: Simplify right side
    511.21x = 346,317.15
  5. Step 5: Solve for x
    x = 346,317.15/511.21
  6. Step 6: Final answer
    x = 677.45

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.